Cyclodextrin compositions, articles, and methods

ABSTRACT

Cyclodextrin compositions including one or more radiation polymerizable monomers and a cyclodextrin inclusion complex, the cyclodextrin inclusion complex including a cyclodextrin compound and an olefinic inhibitor of an ethylene generation in produce, are coated onto packaging materials and cured. Treated containers and treated package inserts having the cured cyclodextrin compositions are useful in packaging of respiring plant materials.

This application is being filed as a continuation application of U.S.patent application Ser. No. 14/619,905, filed Feb. 11, 2015, entitled“Cyclodextrin Compositions, Articles, and Methods,” which is acontinuation application of U.S. patent application Ser. No. 13/896,803,filed May 17, 2013, issued Jul. 7, 2015 as U.S. Pat. No. 9,074,106,which claims priority to U.S. patent application Ser. No. 13/574,287,filed Oct. 11, 2012, which issued Jul. 9, 2013 as U.S. Pat. No.8,481,127, which claims priority to International Patent Application No.PCT/US2011/057017, filed on Oct. 20, 2011, which claims the benefit ofU.S. Provisional Patent Application No. 61/468,041, filed Mar. 27, 2011,each of which is incorporated herein in its entirety.

BACKGROUND

The shelf life of produce or produce materials, including whole plantsand parts thereof including fruits, vegetables, tubers, bulbs, cutflowers and other active respiring plants or plant materials, istypically determined, at least in part, by the amount of an ethylenehormone generated by the respiring plant material. Ethylene is a knownplant ripening or maturation hormone. At any substantial concentrationof ethylene in and around the plant material, the maturation of theplant is initiated, maintained or accelerated, depending onconcentration. Ethylene-sensitive and -insensitive horticulturalcommodities (produce and ornamentals) are categorized as beingclimacteric or non-climacteric on the basis of the pattern of ethyleneproduction and responsiveness to externally added ethylene. Climactericcrops respond to ethylene by an early induction of an increase inrespiration and accelerated ripening in a concentration-dependentmanner. Non-climacteric crops ripen without ethylene and respirationbursts. However, some non-climacteric crops are sensitive to exogenousethylene, which can significantly reduce postharvest shelf life.Non-climacteric produce harbor several ethylene receptors which areactive. Therefore, exposure of non-climacteric produce to exogenousethylene can trigger physiological disorders shortening shelf life andquality. See, Burg et al., Plant Physiol. (1967) 42 144-152 andgenerally Fritz et al. U.S. Pat. No. 3,879,188. Many attempts have beenmade to either remove ethylene from the ambient package atmospheresurrounding the produce or to remove ethylene from the storageenvironment in an attempt to increase shelf life. Reduced ethyleneconcentration is understood to be achieved through a decrease in thestimulus of a specific ethylene receptor in plants. Many compounds otherthan ethylene interact with this receptor: some mimic the action ofethylene; others prevent ethylene from binding and thereby counteractits action.

Many compounds that act as an antagonist or inhibitor block the actionof ethylene by binding to the ethylene binding site. These compounds maybe used to counteract ethylene action. Unfortunately, they often diffusefrom the binding site over a period of several hours leading to a longerterm reduction in inhibition. See E. Sisler and C. Wood, Plant GrowthReg. 7, 181-191 (1988). Therefore, a problem with such compounds is thatexposure must be continuous if the effect is to last for more than a fewhours. Cyclopentadiene has been shown to be an effective blocking agentfor ethylene binding. See E. Sisler et al., Plant Growth Reg. 9, 157-164(1990). Methods of combating the ethylene response in plants withdiazocyclopentadiene and derivatives thereof are disclosed in U.S. Pat.No. 5,100,462 to Sisler et al. U.S. Pat. No. 5,518,988 to Sisler et al.describes the use of cyclopropenes having a C1-4 alkyl group to blockthe action of ethylene.

A suitable olefinic antagonist or inhibitor of receptor sites orethylene generation in produce is 1-methylcyclopropene, derivatives andanalogs thereof have also been tried as an antagonist or inhibitor forthe generation of ethylene from respiring plant or produce material.1-methyl-cyclopropene (1-MCP), 1-butene and other olefins have beenshown to have at least some measurable activity for inhibiting ethylenegeneration and thus extending shelf life. A number of proposals havebeen made for the method of producing and releasing 1-MCP to inhibitethylene release and as a result slowing maturation and maintaining thequality of plant materials. Currently 1-MCP is dispensed by the releaseof 1-MCP from a moisture activated powder or sachet containing complexed1-MCP. In these technologies, 1-MCP is released from a point sourcewhich causes a concentration gradient within the storage chamber thusresulting in a variation in maturation inhibition wherein some producehas an extended life time where other produce exposed to a lesserconcentration 1-MCP tends to have less inhibition of ethylene and has areduced shelf life.

Notwithstanding these efforts, there remains a substantial need in theart for improved plant maturation and degradation prevention. Inparticular, pressure from worldwide urbanization, manufacturing, andpopulation growth necessitates development of new technologies toincrease the efficiency and yield of natural resources expended ondelivering food to the growing global population. In the United States,for example, it is estimated that between 8% and 16% of profit loss offresh produce is due to spoilage and shrinkage which is estimated at $8billion-$28 billion system wide. This loss translates to significantwasted resources, for example pesticides, fertilizer, and herbicide use;land and water use; transportation, including oil and gas use; andresources associated with the storage of produce. Loss of these andother resources are due to inefficiencies in production and deliverythat allows significant spoilage of fruits and vegetables before thesecritical products can reach the consumer. The United Nations Asian andPacific Centre for Agricultural Engineering and Machinery's FeasibilityStudy on the Application of Green Technology for Sustainable AgricultureDevelopment states:

-   -   “Technology is a link that connects sustainability with enhanced        productivity, where natural resource productivity is efficiently        maintained by carefully planning the conservation and        exploitation of resources such as soil, water, plants, and        animals.”        (Feasibility Study on the Application of Green Technology for        Sustainable Agriculture Development, United Nations Asian and        Centre for Agricultural Engineering and Machinery, at p. 20.)        Climate change is raising the stakes for agricultural technology        as the world population grows and the amount of arable land        shrinks. More mouths to feed, plus less arable land and changing        rainfall patterns, means growing demand for technology that lets        farmers do more with less. The European Commission recently        announced an initiative to optimize food packaging without        compromising safety in order to reduce food waste (Harrington,        R., “Packaging placed centre stage in European food waste        strategy,”). The initiative is in response to recent findings        that up to 179 kg of food per person is wasted each year. The        plan stresses the need for innovation, such as “active        packaging” or “intelligent packaging” as one aspect of the        solution.

Technology that addresses the issue of fruit and vegetable spoilage istherefore of critical importance as a “green” technology that reduceswaste of food and its associated resources by increasing the effectiveefficiency of arable land.

BRIEF DESCRIPTION OF THE INVENTION

The invention relates to a packaging material including a cyclodextrincomposition. The cyclodextrin composition contains an effective amountand a controlled release amount of an olefinic inhibitor of ethylenegeneration in produce. The packaging material is coated on at least apart of one surface thereof with the cyclodextrin composition. Aftercoating, the cyclodextrin composition is subjected to electromagneticradiation, such as ultraviolet (UV) radiation, or electron beam (e-beam)radiation. The cyclodextrin composition reacts when exposed to theradiation, such that the composition becomes bonded to the packagingmaterial, or polymerizes to form a polymeric layer or coating on thesurface of the packaging material, or a combination of polymerizationand bonding. The coated and irradiated packaging material is then usedto form containers, packaging, or packaging components or inserts thatgenerate a uniform ethylene inhibiting amount of the olefinic inhibitor,such that live produce stored within the container has a consistentquality and extended useful lifetime. Extending the lifetime of freshproduce can result in significant reduction in food waste. In somecases, packaging material is formed into a container, package, orpackage component; and then the container, package, or package componentis coated with the cyclodextrin composition and irradiated. Theirradiated cyclodextrin compositions form a coating or layer on at leasta portion of the packaging material or container. The coating or layercontains the cyclodextrin inclusion complex with the olefinic inhibitorcompound in the central pore of the cyclodextrin, thereby acting as aneffective source of the olefinic inhibitor.

The invention contemplates a treated article that is a treated packagingmaterial or container having an irradiated cyclodextrin compositiondisposed thereon. The cyclodextrin composition contains an inclusioncomplex. Within the inclusion complex, cyclodextrin molecules contain aneffective amount of the olefinic inhibitor of ethylene generation inproduce. The treated packaging material or container is coated with thecyclodextrin composition and the coated packaging material or containeris irradiated to form a treated packaging material or container. Treatedpackaging material is then formed into a flexible, rigid, or semi-rigidcontainer. The treated container releases olefinic inhibitor into anenclosed volume within a packaging structure such that living plantmaterial contained therein has an extended or more useful life time.

The invention contemplates a cyclodextrin composition including one ormore radiation polymerizable monomers and a cyclodextrin inclusioncomplex containing a cyclodextrin and an olefinic inhibitor. Theinvention also contemplates a cyclodextrin composition including asubstituted cyclodextrin compound, wherein the substituted cyclodextrincompound is reactive to electromagnetic irradiation, and wherein someportion of the substituted cyclodextrin compound includes an inclusioncomplex. The invention also contemplates a radiation cured coating of acyclodextrin composition such that a cyclodextrin compound orsubstituted cyclodextrin is bonded to a polymer chain or backbonewherein some portion of the bonded cyclodextrin compound includes aninclusion complex. The invention also contemplates a radiation curedcoating of a cyclodextrin composition wherein cyclodextrin and/orcyclodextrin inclusion complexes are not part of the radiationpolymerized polymer, but rather are trapped or entangled within thepolymerized coating. The invention also contemplates a packagingmaterial having surface functionalization on at least a part of a majorsurface thereof, wherein the surface functionalization includes aradiation cured cyclodextrin composition.

The invention also contemplates a method of forming an inclusion complexof an olefinic inhibitor with a cyclodextrin to form a cyclodextrincomposition, followed by coating the cyclodextrin composition onto a atleast part of a major surface of a packaging material or container, andirradiating at least the coated portion of the packaging material orcontainer to form a treated sheet or film.

The invention also contemplates that the treated packaging material orcontainer can be manufactured employing a method whereby the treatedpackaging material or container is formed under conditions havingreduced water content.

The invention also contemplates use of the treated packaging material orcontainer to package respiring produce material. The produce material isenclosed within the packaging material or container and the treatedportion of the treated packaging material or container is contacted withan appropriate and activating amount of water such that the cyclodextrinreleases the olefinic inhibiting material at sufficient concentration toinhibit produce ripening or maturation. The olefinic inhibitor is alsoreleased from the treated packaging material or container by exposure toa controlled level of humidity. During distribution and storage when thepackaged produce material storage temperature is low (for example,between about 0° C. to about 14° C.), the humidity in the enclosedvolume around the produce will be high (for example, between about 70%to about 100% relative humidity) due to normal water loss from producerespiration into the enclosed package volume. In many cases, the amountof water vapor exceeds the amount that corresponds to 100% relativehumidity, and liquid water condenses inside the package. The water vaporand/or liquid water released by the produce within the enclosed volumeof the package is sufficient to release the olefinic inhibitor.Alternatively, the internal humidity of the packaging material orcontainer is adjusted by the addition of water prior to sealing thepackage or container to release the olefinic inhibitor. Relativehumidity can be controlled by adding moisture (water mist, spray orsteam) to air by humidifiers during packaging.

The invention further contemplates a container or package for producethat is made from conventional packaging materials and contains apackage insert comprising a section of a treated sheet or film of theinvention that can release the olefinic inhibitor by the increase oraddition of a controlled level of humidity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates headspace concentration of 1-butene as a function oftime.

FIG. 2 illustrates headspace concentration of 1-MCP as a function ofcoating composition.

FIG. 3 illustrates headspace concentration of 1-MCP as a function oftime, varying surface area coated.

FIG. 4 illustrates headspace concentration 1-MCP as a function of time,varying coating composition.

FIG. 5 illustrates headspace concentration of 1-MCP as a function oftime, in the presence of varying amounts of liquid water.

DETAILED DESCRIPTION OF THE INVENTION 1. Definitions

As used herein, the term “cyclodextrin composition” means a compositioncontaining a cyclodextrin inclusion complex that is (1) capable ofcoating a sheet, film, or container and reacting with UV or e-beamradiation to form a treated sheet, film, or container; or (2) is coatedonto a sheet, film, or container; or (3) is a polymerized layer on atleast a portion of a major surface of a sheet, film or container; or (4)is covalently bonded to at least a portion of a major surface of asheet, film or container; or (5) a combination of (3) and (4).

As used herein, the term “cure(d)” or “radiation cure(d)” means toexpose a cyclodextrin composition to electromagnetic radiation orelectron beam radiation under conditions that cause the composition toundergo a reaction such as polymerization, bonding or grafting to apolymer or a surface, crosslinking, or a combination thereof.Electromagnetic radiation includes, but is not limited to, ultraviolet(UV) radiation, microwave radiation, and gamma radiation. “Radiationpolymerizable” or “radiation curable” monomers and crosslinkers arecompounds that are polymerized or crosslinked as a result of interactionwith electromagnetic radiation or electron beam radiation. In someembodiments, radiation polymerizable monomers and crosslinkers are alsopolymerizable by thermal means.

As used herein, the term “cyclodextrin” or “cyclodextrin compound” meansa cyclomalto-oligosaccharide having at least five glucopyranose unitsjoined by an a (1-4) linkage. Examples of useful cyclodextrins includeα-, β-, or γ-cyclodextrin wherein a-cyclodextrin has six glucoseresidues; β-cyclodextrin has seven glucose residues, and γ-cyclodextrinhas eight glucose residues. Cyclodextrin molecules are characterized bya rigid, truncated conical molecular structure having a hollow interior,or pore, of specific volume. “Cyclodextrin” can also includecyclodextrin derivatives as defined below, or a blend of one or morecyclodextrins. The following table recites properties of α-, β-, andγ-cyclodextrin.

CYCLODEXTRIN TYPICAL PROPERTIES CD PROPERTIES α-CD β-CD γ-CD Degree ofpolymerization (n=) 6 7 8 Molecular Size (A°) inside diameter 5.7 7.89.5 outside diameter 13.7 15.3 16.9 height 7.0 7.0 7.0 Specific Rotation[α]²⁵ _(D) +150.5 +162.5 +177.4 Color of iodine complex Blue YellowYellowish Brown Solubility in Distilled water 14.50 1.85 23.20 (g/100mL) 25° C.

As used herein, the term “cyclodextrin inclusion complex” means thecombination of an olefinic inhibitor compound and a cyclodextrin whereinthe olefinic inhibitor compound is disposed substantially within thepore of the cyclodextrin ring. The complexed olefinic inhibitor compoundmust satisfy the size criterion of fitting at least partially into thecyclodextrin internal cavity or pore, to form an inclusion complex. Thecyclodextrin inclusion complexes include, inherent to the formation andexistence of the inclusion complex, some amount of “uncomplexed”cyclodextrin; this is because (1) in embodiments synthesis of theinclusion complex does not result in 100% formation of inclusioncomplex; and (2) in embodiments, the inclusion complex is in equilibriumwith uncomplexed cyclodextrin/uncomplexed olefinic inhibitor. Eachcombination of cyclodextrin and olefinic inhibitor has a characteristicequilibrium associated with the cyclodextrin inclusion complex.

As used herein, the term “cyclodextrin derivative” or “functionalizedcyclodextrin” means a cyclodextrin having a functional group bonded toone of the cyclodextrin glucose moiety hydroxyl groups. One example is agroup that causes the cyclodextrin derivative to be soluble in aradiation polymerizable monomer. Some cyclodextrin derivatives aredescribed, for example, in U.S. Pat. No. 6,709,746.

As used herein, the term “olefinic inhibitor”, “olefinic inhibitorcompound” or “olefinic inhibitor of ethylene generation” is intended tomean an olefinic compound that contains at least one olefinic doublebond, has from about 3 to about 20 carbon atoms and can be aliphatic orcyclic having at least minimal ethylene antagonist or inhibitionactivity.

As used herein, the term “packaging material” means any component ofpackaging in which produce is contained or which is exposed to theenclosed volume within a produce bag or container. Packaging materialincludes, for example, sheets or films from which a package forenclosing produce is made, or any package made for enclosing produce, orany material used on or inside a package. Packaging material includes,for example, thermoplastic packaging films and foils, and wrapping orbags formed therefrom; coated or uncoated paper webs and sheets as wellas bags or cardboard boxes; thermoformed punnets; wax or film coatingsapplied directly to the produce or to a container; multilayer packagingconstructions; printed coatings, embossed indicia, labels placed on orin packaging or on produce, adhesives used to close or seal packaging oradhere labels and the like thereto; ink printed directly on produce,directly on packaging, or on a label that is then adhered to packaging;and the like. In embodiments, one or more packaging materials employedin a package includes a cyclodextrin composition of the invention.

As used herein, the term “treated packaging material” means a packagingmaterial or container that has disposed on at least a portion of a majorsurface thereof a cyclodextrin composition and wherein the cyclodextrincomposition has further been cured.

As used herein, the term “treated package insert” means a piece orsection of a treated packaging material that is inserted into a producepackage or into some other container defining an enclosed volume.

As used herein, the term “treated laminate” or “treated laminatedpackaging material” means a cyclodextrin composition or curedcyclodextrin composition combined with and disposed between on onesurface of a first packaging material and one surface of a secondpackaging material, wherein the first and second packaging materials arethe same or different. In general, treated packaging materials includetreated laminated packaging materials.

As used herein, the term “treated container” or “treated package” means(1) packaging material that has been formed into a flexible, semi-rigid,or rigid container or package to enclose produce, then coated with acyclodextrin composition and cured; or (2) a treated packaging materialthat has been formed into a flexible, semi-rigid, or rigid container orpackage. Treated containers include bags, boxes, cartons, punnets, andother such containers used to package produce material. In conjunctionwith its intended use and for some period of time, the treated containerwill include an enclosed volume. Thus, the treated container will beclosed or sealed to contain an enclosed volume; or will be includedwithin an enclosed volume.

As used herein, the term “treated laminated container” means (1) a firstpackaging material that has been formed into a flexible, semi-rigid, orrigid container to enclose produce, wherein a cured cyclodextrincomposition is combined with and disposed between on one surface of afirst packaging material and one surface of a second packaging material,wherein the first and second packaging materials are the same ordifferent; or (2) a first packaging material that has been formed into aflexible, semirigid, or rigid container to enclose produce, wherein acyclodextrin composition is combined with and disposed between onesurface of the container and a second layer of a packaging material thatis the same or different from the first packaging material, and then thecyclodextrin composition is cured; or (3) a treated laminated packagingmaterial that has been formed into a flexible, semi-rigid, or rigidcontainer. In general, treated containers include treated laminatedcontainers.

As used herein, the term “permeable” as applied to a packaging material,a cured cyclodextrin composition, a treated packaging material, atreated container, a treated laminated packaging material, or a treatedlaminated container means that the material, container, or compositionhas a permeability to the olefinic inhibitor of equal to or greater than0.01 (cm³·mm/m²·24 hrs·bar) at standard temperature and pressure (STP)and 0% relative humidity; or permeability to water vapor of equal to orgreater than 0.1 (g·mm/m²·24 hr) at 38° C. and 90% relative humidity,when measured according to ASTM D96; or permeability to O₂ of equal toor greater than 0.1 (cm³·mm/m²·24 hr·bar) at 23° C. and 0% relativehumidity, when measured according to ASTM D3985; or permeability to CO₂of equal to or greater than 0.1 (cm³·mm/m²·24 hr·bar) at 23° C. and 0%relative humidity, when measured according to ASTM D1434; or acombination thereof. As used herein, the term “impermeable” as appliedto a packaging material, a cured cyclodextrin composition, a treatedpackaging material, a treated container, a treated laminated packagingmaterial, or a treated laminated container means that the material,container, or composition has a permeability to the olefinic inhibitorof less than 0.01 (cm³·mm/m²·24 hr·bar) at STP and 0% relative humidity;or permeability to water vapor of less than 0.1 (g·mm/m²·24 hr) at 38°C. and 90% relative humidity, when measured according to ASTM D96; orpermeability to O₂ of less than 0.1 (cm³·mm/m²·24 hr·bar) at 23° C. and0% relative humidity, when measured according to ASTM D3985; orpermeability to CO₂ of less than 0.1 (cm³·mm/m²·24 hr·bar) at 23° C. and0% relative humidity, when measured according to ASTM D1434; or acombination thereof.

The term “produce” or “produce material” includes any whole plant, plantpart, such as a fruit, flower, cut flower, seed, bulb, cutting, root,leaf, flower, or other material that is actively respiring and, as apart of its maturation, generates ethylene as a maturation hormone(climacteric) or ripens without ethylene and respiration bursts(non-climacteric).

2. Compositions, Articles, and Methods of Making

We have found that one or more cyclodextrin compounds are useful to forma cyclodextrin composition using mild conditions. The cyclodextrincompositions are useful to form a coating on at least a portion of amajor surface of one or more packaging material or containers. Aftercoating a cyclodextrin composition on at least a portion of a surface ofa packaging material or container, the coated surface is irradiated withUV or e-beam radiation to form a treated sheet, film, or container. Insome embodiments the treated packaging material is used to form acontainer. In other embodiments the treated packaging material is usedto form a treated package insert, wherein a section of the treatedpackaging material is attached to or simply inserted into a producecontainer. The treated container, or a container having a treatedpackage insert disposed within its interior, is used to package produce.

Using the compositions, articles, and methods of the invention enablesolefinic inhibitor compounds to be employed in a safe, convenient, andscalable manner that avoids subjecting the cyclodextrin inclusioncomplex to harsh conditions that can cause loss of the olefinicinhibitor from the cyclodextrin inclusion complex. Further, the treatedpackaging material, containers, and package inserts of the inventionimpart low but constant levels of olefinic inhibitor release therefromwhen disposed within an enclosed volume in the presence of water vaporand thus provide long term inhibition of ripening or maturation of theproduce while disposed inside the enclosed volume.

The cyclodextrin compositions of the invention include at least acyclodextrin inclusion complex and a monomer. In embodiments, thecyclodextrin inclusion complex is simply admixed with the monomer at thedesired ratio to form the cyclodextrin composition.

The cyclodextrin employed to form the cyclodextrin inclusion complex isselected for the specific volume of the cyclodextrin pore. That is, thecyclodextrin pore size is selected to fit the molecule size of theolefinic inhibitor. The olefinic inhibitor is a compound having from 3to about 20 carbon atoms, comprising at least one olefinic bond andcomprising a cyclic, olefinic or diazo-diene structure. Examples ofcompounds useful as the olefinic inhibitor of ethylene generationinclude 1-methyl cyclopropene, 1 butene, 2-butene, and isobutylene. Ofthese, 1-methyl cyclopropene, or 1-MCP has been found to be particularlyuseful. It has been found that 1-MCP has a molecular size that issuitable for formation of an inclusion complex when combined withα-cyclodextrin, or α-CD. In embodiments, the inclusion complex containsabout 0.10 to 0.99 mole of the olefinic inhibitor per mole ofcyclodextrin, or about 0.20 to 0.95 mole of the olefinic inhibitor permole of cyclodextrin, or about 0.30 to 0.90 mole of the olefinicinhibitor per mole of cyclodextrin, or about 0.50 to 0.90 mole of theolefinic inhibitor per mole of cyclodextrin, or about 0.50 to 0.80 moleof the olefinic inhibitor per mole of cyclodextrin, or about 0.30 to0.70 mole of the olefinic inhibitor per mole of cyclodextrin.

Methods of forming cyclodextrin inclusion complexes are known and aredescribed, for example, in U.S. Pat. Nos. 6,017,849 and 6,548,448 aswell as in Neoh, T. Z. et al., J. Agric. Food Chem. 2007, 55,11020-11026. Typically the cyclodextrin and the olefinic inhibitor aremixed together in a solution for a period of time sufficient to form theinclusion complex. In the case of 1-MCP and α-cyclodextrin,α-cyclodextrin is dissolved in water and 1-MCP is bubbled into thesolution for a period of time at room temperature. The inclusion complexprecipitates from the solution as it forms and thus is easily isolatedby simple filtration followed by vacuum drying. The dried cyclodextrininclusion complex is then ready for use. Storage in a dry container withminimal head space is sufficient.

In some embodiments, the cyclodextrin inclusion complex is formed with acyclodextrin derivative. Cyclodextrin derivatives are employed to formthe inclusion complex in some embodiments to improve miscibility in thecyclodextrin composition. Cyclodextrin derivatives employed to improvemiscibility of the cyclodextrin composition include any of thecyclodextrin derivatives described in U.S. Pat. No. 6,709,746 or inCroft, A. P. and Bartsch, R. A., Tetrahedron Vol. 39, No. 9, pp. 14171474 (1983). In some embodiments where a cyclodextrin derivative isemployed to form the cyclodextrin inclusion complex, the olefinicinhibitor is introduced in a non-water solvent, for example ahydrocarbon having 1 to 10 carbons, an alcohol having 1 to 10 carbons, aheterocyclic or aromatic solvent having 4 to 10 carbons. In some suchembodiments, blends of one or more solvents are employed. In otherembodiments, the inclusion complex is formed prior to functionalizationof the cyclodextrin derivative. In such embodiments, care must be takenduring the functionalization to employ techniques and select functionalgroup chemistries that avoid displacing the olefinic inhibitor from theinclusion complex, for example by preferential inclusion of one of thecompounds employed in the functionalization.

Monomers useful in forming the cyclodextrin compositions include any ofthe known compounds having one or more unsaturated bonds that arepolymerizable by free radical polymerization methods or plasmapolymerization methods such as electron beam radiation polymerization.In embodiments, useful vinyl monomers include acrylates, methacrylates,acrylamides, allylic monomers, α-olefins, butadiene, styrene and styrenederivatives, acrylonitrile, and the like. Some examples of usefulmonomers include acrylic acid, methacrylic acid, and alkyl esters ofacrylic or methacrylic acid wherein the ester groups have between 1 and18 carbons, in some embodiments between 1 and 8 carbons, and are linear,branched, or cyclic. In embodiments, blends of two or more monomers areemployed in the cyclodextrin compositions. In some such embodiments, oneor more monomers are selected for improved wetting, adhesion, or both ofthe cyclodextrin composition to the target substrate. In some suchembodiments, one or more monomers are selected to provide specificpermeability properties. In some embodiments, monomers are selected toprovide a targeted permeability of the cured cyclodextrin composition towater, or to the olefinic inhibitor, or both. Careful control ofpermeability is selected for optimum controlled release of the olefinicinhibitor during use. Various additional components, as are describedbelow, are further selected to control olefinic inhibitor releaseproperties and other physical properties of the cured cyclodextrincompositions of the invention.

In some embodiments, monomers having more than one unsaturated andpolymerizable bond are employed in the cyclodextrin compositions, forexample diacrylates such as ethylene glycol diacrylate, hexanedioldiacrylate, and tripropyleneglycol diacrylate; triacrylates such asglycerol triacrylate and trimethylolpropane triacrylate; andtetraacrylates such as erythritol tetraacrylate and pentaerythritoltetraacrylate; divinyl benzene and derivatives thereof, and the like.Such monomers provide crosslinking to the cured cyclodextrincomposition. Other compounds that are useful monomers where UVpolymerization is employed include photoactive crosslinking agents.Photoactive crosslinking agents include, for example, benzaldehyde,acetaldehyde, anthraquinone, substituted anthraquinones, variousbenzophenone-type compounds and certain chromophore-substitutedvinylhalomethyl-s-triazines, such as2,4-bis(trichloromethyl)-6-p-methoxystyryl-s-triazine. In some suchembodiments, a monomer having more than one unsaturated andpolymerizable bond, or a photoactive crosslinker, is present at lessthan about 10% by weight of the cyclodextrin composition, for example atabout 0.1% to 5% by weight of the cyclodextrin composition. Inembodiments, the monomer or blend of monomers is a liquid at thetemperature at which the cyclodextrin composition is coated onto athermoplastic sheet, film, or container. In some embodiments, thecyclodextrin, the cyclodextrin inclusion complex, or both are misciblein the monomer or monomer blend.

The cyclodextrin composition is an admixture of the cyclodextrininclusion complex and one or more monomers, and optionally one or morecrosslinking agents, along with any additional components desirablyincluded in the cyclodextrin composition. In embodiments, the amountcyclodextrin inclusion complex employed in the cyclodextrin compositionis about 0.001% by weight to 25% by weight of the composition, or about0.01% by weight to 10% by weight of the composition, or about 0.05% byweight to 5% by weight of the composition. The amount of cyclodextrininclusion complex included in a particular formulation is selected basedon the amount of olefinic inhibitor desired in the enclosed space withinthe treated container, in conjunction with variables such as thepermeability of the coating to water and the olefinic inhibitor.Criteria informing this selection are described in greater detail below.

In embodiments, one or more additional components are added to thecyclodextrin composition. Adhesion promoters, antifouling agents,thermal or oxidative stabilizers, colorants, adjuvants, plasticizers,and small amounts of solvents are examples of additional materials thatare added to the cyclodextrin compositions in some embodiments. In someembodiments, the cyclodextrin composition includes a polymerizationinitiator. In some embodiments where curing is carried out by UVradiation, it is desirable to include a photoinitiator that will absorbthe UV radiation and become activated, thereby initiating thepolymerization of the unsaturated polymerizable monomer(s) and any othercomponents of the cyclodextrin composition that contain UV polymerizablemoieties. In many embodiments, a photoinitiator is selected based on thewavelength of UV radiation to be employed. Where a photoinitiator isemployed, it is included in the cyclodextrin compositions at about 0.01%by weight to 5% by weight based on the weight of the cyclodextrincomposition, for example 0.5% by weight to 2% by weight based on theweight of the cyclodextrin composition. Examples of suitablephotoinitiators include those sold under the trade name IRGACURE® byCiba Specialty Chemicals Corp. of Tarrytown, N.Y.; those sold under thetrade name CHEMCURE® by Sun Chemical Company of Tokyo, Japan; andLUCIRIN® TPO sold by BASF Corporation of Charlotte, N.C.

In some embodiments, an additional component is a prepolymer.Prepolymers are either formed in situ from the cyclodextrin compositionby prepolymerization thereof, optionally followed by addition of moremonomer and photoinitiator, or are added to the cyclodextrin compositionin order to increase coating viscosity of the composition prior tocuring. Prepolymerization is a bulk or continuous polymerization methodwherein a minor amount of polymerization, for example 1% to 10%, of thebulk coating composition is carried out to achieve a target viscosity.The prepolymers are of any suitable molecular weight and are soluble inthe monomer or monomers of the cyclodextrin composition. Prepolymers areformed in situ or added to the cyclodextrin composition at any amountthat is useful to provide the target coating viscosity. In a typicalprepolymerization, a cyclodextrin composition is subjected to UVradiation in bulk or continuous mode until the desired viscosity isreached, forming a prepolymerized cyclodextrin composition. In someembodiments, targeted viscosities for the prepolymerized cyclodextrincompositions are from about 10 cP to 2000 cP, or about 100 cP to 1000cP. In embodiments, one or more additional monomers, crosslinkers,initiators, or a combination thereof are then added to theprepolymerized cyclodextrin composition. The prepolymerized cyclodextrincomposition is then coated and cured, wherein the viscosity of theprepolymerized cyclodextrin composition allows a thicker layer to becoated than would be practicable using the cyclodextrin compositionwithout prepolymerization. In embodiments, coatings 25 microns andthicker of prepolymerized cyclodextrin composition are formed, forexample between about 25 microns and 100 microns. Such coatingthicknesses are useful, for example, where the cured cyclodextrincomposition is a pressure-sensitive adhesive. In some embodiments, thecyclodextrin inclusion complex is added to the coating composition afterprepolymerization; however, in many embodiments the cyclodextrininclusion complex is added prior to prepolymerization because mixing ofthe components is more easily accomplished prior to forming a higherviscosity composition.

In some embodiments, an additional component is a water scavenger. Awater scavenger is a compound that is soluble or dispersible in thecoating composition to be cured, and is available to reactpreferentially with water molecules such that it effectively acts toscavenge ambient moisture from airborne humidity during standardprocessing conditions. The amount of water scavenger added should be aminimum amount to react with ambient moisture during processing. This isbecause, in the envisioned packaging applications wherein thecyclodextrin compositions are included in a produce container, water isrequired to facilitate release of the olefinic inhibitor into thecontainer. Thus, an amount of water scavenger should be provided in thecyclodextrin composition that is quickly depleted once a substantialamount of water vapor is encountered. Examples of water scavengerssuitably employed in the cyclodextrin compositions of the inventioninclude various orthoesters and hexamethyldisilazane. In embodiments,about 1 wt % or less based on the total cyclodextrin composition weightof the water scavenger is added to the cyclodextrin compositions, forexample about 0.01 wt % to 1 wt % based on the total cyclodextrincomposition weight or about 0.05 wt % to 0.5 wt % based on the totalcyclodextrin composition weight.

In some embodiments, an additional component is a desiccant. In thepresent invention, desiccants are employed to scavenge water from theinterior of an enclosed volume into which a respiring produce materialis expected to generate an excess of the desired amount of water. Theeffects of excess water are described in more detail below. Desiccantsare also added, in some embodiments, directly to the interior of atreated container or treated laminated container of the inventionseparately from the cyclodextrin composition itself; however, in someembodiments, the desiccant is added directly into the cyclodextrincomposition for convenience and/or efficiency. Suitable desiccantmaterials include, for example, silica gel and molecular sieve typedesiccants. The amount of desiccant incorporated within a cyclodextrincomposition or cured cyclodextrin composition is not particularlylimited and is selected based on the particular end use, that is, thetype of package, volume of enclosed space, type of produce to bepackaged, and the like. In general, the amount of desiccant is selectedto be about 0.001 wt % to 99 wt % based on the total weight of thecyclodextrin composition, or about 0.1 wt % to 50 wt % based on thetotal weight of the cyclodextrin composition, or about 1 wt % to 10 wt %based on the total weight of the cyclodextrin composition.

The packaging materials that are suitably coated with a cyclodextrincomposition on at least a portion thereof include any packaging materialthat is suitable for surface coating followed by curing with UV ore-beam radiation. Suitable packaging materials include paper andcardboard and other natural and synthetic biomass-based packagingmaterials, as well as synthetic petroleum-based thermoplastic polymericfilms, sheets, fibers, or woven or nonwoven fabrics that are useful aspackaging materials for produce, and composite materials including oneor more thereof. Some examples of packaging materials usefully employedto form containers, labels, laminates (i.e. treated laminated packagingmaterials) or package inserts include paper, cardboard, coated paper orcardboard such as extrusion coated paper or cardboard, chipboard,nonwoven or woven fabrics, wood/thermoplastic composites, polyvinylhalides such as poly(vinyl chloride) (plasticized and unplasticized) andcopolymers thereof; polyvinylidene halides such as polyvinylidenechloride and copolymers thereof; polyolefins such as polyethylene,polypropylene, and copolymers and morphological variations thereofincluding LLDPE, LDPE, HDPE, UHMWPE, metallocene polymerizedpolypropylene, and the like; polyesters such as polyethyleneterephthalate (PET) or polylactic acid (PLA) and plasticized variationsthereof; polystyrene and copolymers thereof including HIPS; polyvinylalcohol and copolymers thereof; copolymers of ethylene and vinylacetate; and the like. Blends, alloys, crosslinked versions thereof, andcomposites thereof are also useful in various embodiments. Two or morelayers of such packaging materials are present in some embodiments asmultilayer films or carton constructions.

The packaging materials contain, in some embodiments, one or morefillers, stabilizers, colorants, and the like. In some embodiments thepackaging materials have one or more surface coatings thereon. In someembodiments the packaging material has a surface coating thereon priorto coating the cyclodextrin composition. Surface coatings includeprotective coatings such as wax, acrylic polymer coatings, and the like;coatings to render surfaces printable; coatings to render otherwisepermeable packaging materials impermeable; adhesive coatings; primers;tie layer coatings; metalized or reflective coatings; and the like. Thetype and function of surface coatings are not particularly limitedwithin the scope of the invention; likewise the manner in which thesurface coatings are applied is not particularly limited. In variousembodiments where a surface coating will be exposed to the enclosedvolume within a produce package, the surface coating is subsequentlycoated with the cyclodextrin composition.

In one such commercially important embodiment, commercial growers anddistributors commonly use polyethylene extrusion coated recyclablepaperboard or carton board packaging to ship produce. The polyethylenecoating provides water resistance and water vapor protection in thegenerally moist and humid environments that are typical of shipping andstorage conditions for fresh fruits and vegetables. Printed paperboardpackaging can range from bulk bins to specialized display cartons.Printed indicia are, in some embodiments, embossed indicia. Theextrusion coated surface provides an opportunity to include acyclodextrin composition of the invention.

In some embodiments the packaging material is treated with a plasma orcorona treatment prior to coating the cyclodextrin composition. Suchsurface treatments are well known in the industry and are often employedin the industry to modify the surface energy of packaging materials, forexample to improve wetting or adhesion of coatings or printed materialsto the surface of a packaging material. Such surface treatments arelikewise useful in some embodiments to improve wetting and adhesion ofthe cyclodextrin compositions to the packaging material.

In some embodiments, the packaging material is treated with a primerprior to coating the cyclodextrin composition. In some such embodimentsfilms and sheets of thermoplastics used as packaging materials areobtained already pre-coated with a primer; a wide variety of such filmsand sheets are available in the industry and are targeted for improvingadhesion of various types of coatings thereto. In some embodiments aplain film or sheet is coated “in line” with a primer designed toimprove adhesion of radiation polymerizable coatings prior to coatingthe cyclodextrin composition. A plethora of such coatings andtechnologies are available and one of skill will understand that primercoatings are optimized for each coating formulation and each film orsheet type. Some examples of primer compositions suitably disposedbetween the packaging material surface and the cyclodextrin compositionsof the invention include polyethyleneimine polymers such aspolyethyleneimine, alkyl-modified polyethyleneimines in which the alkylhas 1 to 12 carbon atoms, poly(ethyleneimineurea), ethyleneimine adductsof polyaminepolyamides, and epichlorohydrin adducts ofpolyaminepolyamides, acrylic ester polymers such as acrylamide/acrylicester copolymers, acrylamide/acrylic ester/methacrylic ester copolymers,polyacrylamide derivatives, acrylic ester polymers containing oxazolinegroups, and poly(acrylic ester)s. In embodiments, the primer compositionis an acrylic resin, a polyurethane resin, or mixture thereof. Inembodiments the primer composition includes at least one radiationcurable polymer, oligomer, macromonomer, monomer, or mixture of one ormore thereof.

In some embodiments the packaging material is a sheet or film that isformed into a container suitable to enclose produce within an enclosedspace. In other embodiments the packaging material is a sheet or filmthat is converted into coupons, strips, tabs, and the like for thepurpose of insertion into the enclosed space defined by an otherwiseuntreated produce container. In some embodiments the coupons, strips,tabs, and the like are labels that are adhesively applied to the produceor the container. In some such embodiments, the coupons, strips, tabs,and the like are labels that are further printed with one or moreindicia. In embodiments, the indicia are embossed indicia. Thecyclodextrin composition is present, in various embodiments, on anysurface that is directly or indirectly exposed to the enclosed space. Insome embodiments, the packaging material is a treated laminate. In someembodiments the treated laminate is permeable to the olefinic inhibitoron a first side thereof and is impermeable to the olefinic inhibitor ona second side thereof. In some embodiments, the packaging material is atreated laminate that is permeable to water on at least a first sidethereof.

Containers suitable to enclose produce within an enclosed space include,for example, bags, boxes, cartons, pallets, and punnets. In someembodiments, the package is designed to contain a single item ofproduce, such as a bag to contain a banana or a head of lettuce; inother embodiments, the package is a carton to contain multiple items,such as a carton to contain a bushel of apples or several pints ofberries; in still other embodiments, the container is designed toenclose a pallet of smaller produce boxes or punnets, such as largepolyethylene bags that enclose a pallet of berries for transport. Instill other embodiments, the container is a truck, boat, or planewherein a sealed and/or controlled environment is provided for transportof produce.

In many embodiments, more than one packaging material is employed informing a container; in such embodiments the cyclodextrin composition ispresent on one or more packaging component. In an illustrative example,a semi-rigid polypropylene container is filled with produce and thensealed with a polyvinyl chloride film. The produce includes a paperlabel attached to the produce. Within the container is a polyester pouchor cup containing a sauce, dressing, or other condiment. The pouch orcup has indicia printed thereon. In this example, the cyclodextrincomposition is present on all or a portion of an inner surface of thecontainer or the film, an outer surface of the cup or pouch or the paperlabel, and/or included in the ink that is printed on the cup or pouch.Alternatively, the cyclodextrin composition is included on a packageinsert or label that is separately added to the container prior tosealing with the film. In some embodiments, a combination of more thanone such surface includes the cyclodextrin composition. In yet anotherillustrative example, a polyethylene extrusion coated paperboard cartonis coated or printed on a surface thereof with a cyclodextrincomposition, followed by curing. The paperboard carton is then filledwith produce, stacked on a pallet with a plurality of other cartons, andthe pallet is enclosed in a polyethylene bag. In some embodiments, allof the cartons include the cured cyclodextrin composition; in otherembodiments, only one or some percent of the cartons include the curedcyclodextrin composition. In some examples of this technology, the bagfurther contains a controlled atmosphere or a modified atmosphere, or isa selectively permeable membrane material. Such atmosphere variationsand permeable membrane materials are discussed in detail below. In someembodiments, the bag further contains a desiccant in a pouch or sachet.

In yet another representative example, a plastic bag containing produceis a treated laminated container, that is, the cured cyclodextrincomposition does not directly contact the interior of the container. Thecyclodextrin composition is cured directly on a first packaging materialwith a second packaging material applied on top of the cyclodextrincomposition and cured after lamination to form a treated laminate; thetreated laminate is then formed into a bag. The packaging material thatforms the exterior of the bag is impermeable to the olefinic inhibitor.The packaging material contacting the interior of the bag is permeableto at least the olefinic inhibitor. At least one of the packagingmaterials is permeable to water vapor. In a related example, the treatedlaminate is a film for wrapping e.g. a carton or other container forproduce material. In another related example, the cyclodextrincomposition is cured directly on a first packaging material with asecond packaging material applied on top of the cyclodextrin compositionand cured after lamination to form a treated laminate; the laminate istentered (oriented, or stretched) monoaxially or biaxially either beforeor after the cyclodextrin composition is cured. After cure andtentering, the treated laminate is formed into a bag or used as a wrapfor a produce container. In yet another related example, the curedcyclodextrin composition is a pressure sensitive adhesive disposed on apackaging material; the pressure sensitive adhesive is affixed to acontainer to form a treated laminated container. The pressure sensitiveadhesive is adhered to the interior or exterior side of the container toform a treated laminated container.

In some embodiments, the packaging material is directly applied to theproduce, for example as a continuous or discontinuous coating, or aspart of an adhesive or in printed characters on a printed or reverseprinted produce label. In such embodiments, all or a portion of thecoating or label contains the cyclodextrin composition. In someembodiments, an adhesive used to adhere a label on produce or on apackage, or to seal a package, includes the cyclodextrin composition.The label is adhered to the interior or exterior of the package; thatis, the surface contacting the interior of the enclosed volume, or thesurface that does not contact the interior of the enclosed volumedirectly but only indirectly, e.g. via permeability of the packagingmaterial to water and/or the olefinic inhibitor. Such constructions areembodiments of treated laminated containers. Treated laminatedcontainers include those having a cured cyclodextrin composition isdisposed between one surface of the container and a second layer of apackaging material that is the same or different from the firstpackaging material that is the packaging material from which thecontainer is formed. In such embodiments, cyclodextrin composition isgenerally not in direct contact with the interior, enclosed volume ofthe container; that is, it is disposed between two layers of packagingmaterial. Thus, the packaging material surface in contact with theproduce and also in contact with the cured cyclodextrin composition mustbe permeable to water and the olefinic inhibitor in order for theolefinic inhibitor to be released from the cyclodextrin inclusioncomplex and into the interior volume of the container. In some suchembodiments, the laminate structure is permeable to the olefinicinhibitor on a first side thereof and is impermeable to the olefinicinhibitor on a second side thereof; in some embodiments the container isa treated laminated container wherein the laminate structure ispermeable to water on at least a first side thereof.

In some embodiments, the packaging material itself is permeable to theolefinic inhibitor. In some such embodiments, the cyclodextrincomposition is coated on, or contacted to, the exterior of the packagevia lamination, and the olefinic inhibitor is released such that itdiffuses through the package into the interior space where the produceis situated. In some such embodiments, the packaging material is alsowater permeable and the release of the olefinic inhibitor is controlledby water vapor permeating the packaging material from the interior ofthe enclosed volume; in other such embodiments, the packaging materialis impermeable to water and release of the olefinic inhibitor iscontrolled by ambient humidity that exists exterior to the enclosedvolume. In some embodiments, the packaging material is not permeable tothe olefinic inhibitor. In such embodiments, the packaging material is abarrier that prevents the escape of the olefinic inhibitor from theenclosed space defining the produce package. In still other embodimentsthe packaging material itself is permeable to the olefinic inhibitor,but one or more surface treatments, coatings, or layers (in the case ofa multilayer film or carton, for example) provide a barrier function.

In treated laminated containers, two different packaging materials areemployed in some embodiments as the first and second packaging materialsbetween which the cyclodextrin composition is sandwiched; as such, thepackaging materials can be of differentiable permeability. Thus, forexample, the interior-facing side of the laminate is permeable to theolefinic inhibitor but in some embodiments is impermeable to water,whereas the exterior facing side of the laminate is impermeable to theolefinic inhibitor and in some embodiments is permeable to water. Insome such embodiments, a controlled humidity atmosphere provided outsidethe container—such as in a storage facility—is used to control the rateof release of the olefinic inhibitor, instead of the interior atmospherewithin the container itself.

The cyclodextrin compositions are coated onto the surface of a packagingmaterial, or directly onto produce, and cured. Coating is accomplishedusing any of the known coating technologies available in the industrywherein mixtures of curable monomers are coated prior to curing. In someembodiments coating is accomplished without employing elevatedtemperatures, that is, by employing ambient temperatures of a processingfacility. In other embodiments, the temperature during coating andcuring is between about 5° C. and 75° C., or between about 0° C. and 25°C. Useful coating techniques employed to coat the cyclodextrincompositions include, for example, die coating, curtain coating, floodcoating, gap coating, notch bar coating, wrapped wire bar drawdowncoating, dip coating, brush coating, spray coating, pattern coating suchas rotogravure coating, and print coating employing printingtechnologies such as flexographic printing, inkjet printing,lithographic printing techniques, letterset printing, and screenprinting. The viscosity profile of the cyclodextrin compositionincluding properties such as shear thinning, the shape and compositionof the packaging material or produce, and the desire to coat theentirety vs. a portion of a surface dictates which of the known coatingtechnologies are useful to coat the cyclodextrin compositions. Forexample, die coating, notch bar coating, and the like are usefullyemployed to coat the entirety of a substantially planar web of packagingmaterial, whereas in embodiments where only a portion of a surface is tobe coated, or coating onto a formed container or onto produce isdesirable, one or more spray, dip, or print coating technologies isdesirably employed. Where only one specific portion of a packagingmaterial is to be coated, print coating or in some embodimentsrotogravure coating is desirably used. In some such embodiments, theprint coating is embossed indicia.

Radiation curable inks, such as UV curable inkjet and flexographic inks,are known in the industry and such apparatuses to apply and cure suchinks are easily obtained. Further, radiation curable ink formulationsare easily modified to include the amount of the cyclodextrin inclusioncomplex necessary to accomplish delivery of the needed amount ofcomplexed olefinic inhibitor to a surface of one or more packagingmaterials. Thus, in one embodiment of the invention, a UV curable inkjetink is modified to include an amount of a cyclodextrin inclusioncomplex, for example by admixing the cyclodextrin inclusion complex intothe ink; the modified inkjet ink is delivered over a target area to thepackaging material and cured to provide a treated packaging material.Other printing techniques, for example flexographic printing, are alsoof utility in delivering a precise and reproducible amount ofcyclodextrin inclusion complex to a packaging material by similarlyincorporating the inclusion complexes containing the olefinicinhibitors. Large scale production of packaging will, in someembodiments, realize greater efficiency with flexographic printinginstead of inkjet printing.

The desired thickness of the coated cyclodextrin composition layer isdictated by the amount of cyclodextrin inclusion complex in thecyclodextrin composition, the inherent equilibrium ratio of thecyclodextrin inclusion complex with uncomplexed olefin inhibitor, thepermeability of the cured cyclodextrin composition to the olefinicinhibitor, the viscosity or coating thickness requirements of thetechnique employed to coat the cyclodextrin composition, the size of theportion of surface area containing the cured cyclodextrin composition,the type of produce to be packaged, and the volume of the enclosed spacesurrounding the produce. In sum, the coating thickness is selected toprovide an amount of cyclodextrin inclusion complex that is effective toprovide a suitable atmospheric (gaseous) concentration of the olefinicinhibitor to the enclosed space such that the useful life of the produceis extended. In some embodiments, an effective amount of olefinicinhibitor in the atmosphere within the enclosed space of the producecontainer is between about 2.5 parts per billion (ppb) to about 10 partsper million (ppm), or between about 25 ppb and 1 ppm. In variousembodiments, the coating thickness is between about 0.001 micrometer(μm) and 10 millimeter (mm) thick, or between about 0.01 μm and 1 mmthick, or between about 0.1 μm and 0.5 mm thick, or between about 1 μmand 0.25 mm thick, or between about 2 μm and 0.1 mm thick.

Once the cyclodextrin composition is coated onto a packaging material,it is cured in situ to form a treated packaging material. In situ curingis accomplished without the need to employ elevated temperatures;however, in some embodiments elevated temperatures are suitablyemployed; the curing process is not particularly limited as to thetemperature employed. For example, in embodiments, the temperatureemployed during cure of the cyclodextrin composition is about 0° C. to135° C., or about 30° C. to 120° C., or between about 50° C. to 110° C.Maintaining both coating and curing temperatures at or below about 100°C. is easily accomplished. In embodiments where the cyclodextrininclusion complex is 1-MCP complexed with α-cyclodextrin, elevatedtemperatures do not cause appreciable release of the olefinic inhibitorfrom the cyclodextrin inclusion complex.

In some embodiments, in situ curing is accomplished employing UVradiation. UV radiation is electromagnetic radiation having a wavelengthof between 10 nm and 400 nm. In embodiments, wavelengths between about100 nm and 400 nm are useful; in other embodiments wavelengths betweenabout 200 nm and 380 nm are useful. Wavelength, as well as radiationintensity and time of exposure, is selected based on processingparameters such as the absorption characteristics of the photoinitiatoremployed, polymerization kinetics of the monomer(s) selected, andthickness of the cyclodextrin composition coating. Suitablephotoinitiators and amounts thereof employed in the cyclodextrincompositions are described above. Useful methodologies and criteria toconsider in UV curing are described, for example, in U.S. Pat. No.4,181,752.

In embodiments, curing is accomplished in an environment that issubstantially free of atmospheric moisture, air, or both. Such anenvironment is achieved, in some embodiments, by purging the coated areawith an inert gas such as carbon dioxide or nitrogen during the curing.In other embodiments, most conveniently where the coated packagingmaterial is a flat sheet or film, water and air are suitably excludedduring cure by applying a UV-transparent, water impermeable liner on topof the coated, uncured cyclodextrin composition. The coated cyclodextrincomposition is cured by irradiating through the liner; then the liner isremoved e.g. to facilitate windup of the treated packaging film orsheet, wherein the film or sheet layers provide a suitable waterbarrier. In other embodiments the liner is left on top of the treatedpackaging material until it is employed as a treated container ortreated package insert, at which point the liner is removed. The linermaterial is not particularly limited in composition or thickness and isselected for UV transparency at the desired wavelength. In embodiments,the liner is selected to have a sufficiently low level of adhesion tothe cured cyclodextrin composition that the liner can be removed aftercure without appreciable damage to the cured cyclodextrin composition.In some embodiments, the liner is added after cure to facilitate storageof the treated packaging material or treated container; in such cases,the liner does not need to be transparent to radiation but rather isselected primarily to exclude water.

In some embodiments, curing of the coated cyclodextrin composition isaccomplished employing electron beam, or e-beam, radiation. In otherembodiments, prepolymerization of the cyclodextrin composition isfollowed by coating onto a packaging material, and subjecting to e-beamradiation in order to crosslink the cyclodextrin composition. In somesuch embodiments, additional monomers, including monomers with more thanone polymerizable moiety, are added to the prepolymerized cyclodextrincomposition prior to coating and subjecting to e-beam radiation. E-beammethods employed to polymerize the cyclodextrin composition aredescribed, for example, in the web article by Weiss et al., “PulsedElectron Beam Polymerization”, posted Jan. 1, 2006. Numerous methods ofpolymerization and/or crosslinking facilitated by e-beam are describedin both patent and non-patent literature. Some examples of methodsuseful to polymerize and/or crosslink the cyclodextrin compositions ofthe invention include, for example, U.S. Pat. Nos. 3,940,667; 3,943,103;6,232,365; 6,271,127; 6,358,670; 7,569,160; 7,799,885, and the like.

E-beam is a high energy ionizing radiation that creates free radicalsand is capable of penetrating materials that are opaque to UV radiation.As such, use of e-beam polymerization or crosslinking presents thepossibility of grafting components of the cyclodextrin composition tothe packaging material directly. Many of the packaging materials listedabove, for example polyolefin, polyvinyl chloride, and polystyrene, aresusceptible to e-beam radiation; that is, one or more free radicals areformed along the polymer backbone in some cases by e-beam irradiation.Free radical formation along the polymer backbone, in turn, presents anopportunity for the polymer backbone to bond to one or more componentsof the cyclodextrin composition. In embodiments, one or more monomers orcyclodextrin inclusion complexes are bonded, or grafted, to thepackaging material by employing e-beam mediated polymerization or e-beammediated crosslinking. The dose of radiation delivered is carefullyadjusted in each case to avoid domination by the competing process ofchain scission.

In the manufacture of the cyclodextrin compositions of the inventionwhere the cyclodextrin composition comprises the cyclodextrin inclusioncomplex formed from 1 MCP and α-cyclodextrin (1-MCP/c/α-CD), we havefound that careful control of water content during coating, curing, andsubsequent storage prior to use is useful in maintaining the stabilityof the 1-MCP/c/α-CD complex. As water is reduced, the 1-MCP is morecontrollably maintained within the central pore of the α-cyclodextrin.Storage of treated packaging materials containing 1-MCP/c/α-CD isadvantageously accomplished by either covering the treated portion ofthe treated packaging material with a liner that is impermeable to watervapor; or in the case of treated films or sheets formed from water vaporimpervious thermoplastics, winding the films or sheets into rolls, orstoring sheets or containers in stacks; or otherwise containing thetreated packaging materials in a low humidity environment. In someembodiments, bulk quantities of treated packaging materials, such asrolls of treated packaging film or nested stacks of treated containers,are wrapped in water impervious plastic or foil wrappers or enclosed inwater impermeable bags for storage and/or shipping.

In some embodiments, where a liner is applied over the curedcyclodextrin compositions, the liner includes one or more desiccants. Insome such embodiments, the desiccants are embedded in, or adhered to,the liner. The desiccant is employed along with the liner itself toexclude water during storage and/or shipping. Examples of desiccantsthat are suitably employed include silica gel, activated charcoal,calcium sulfate, calcium chloride, montmorillonite clay, and molecularsieves. The desiccant is attached to the liner in such a manner that itremains substantially attached to the liner when the liner is removedfrom the treated packaging material or treated container.

In some embodiments, a treated packaging material or a treated laminateis stretched before or after curing the cyclodextrin composition.Monoaxial or biaxial stretching, or tentering, of thermoplastic filmforming materials and laminates formed from such materials is carriedout as an efficient and economical way to form thin films with enhancedstrength. Where the cyclodextrin composition is applied to athermoplastic film prior to tentering, a relatively thick coating and/ora high concentration of the cyclodextrin inclusion complex is employedbecause the layer containing the cyclodextrin inclusion complex ispredictably made thinner at the prescribed stretch ratio.

3. Uses of the Compositions, Methods, and Articles

The treated packaging materials and treated containers are usefullyemployed in enclosing produce. The treated package inserts are usefullyincluded within the enclosed volume of packaged produce. In embodiments,the treated packaging material, treated container, or treated packageinsert is arranged such that the cured cyclodextrin composition contactsthe interior atmosphere of the enclosed volume surrounding one or moreproduce items, the enclosed volume being provided by the container. Thetype and conformation of the produce container is not particularlylimited; any bag, box, punnet, tub, cup, pallet bag, transportationinterior (e.g. truck interior), etc. that defines an enclosed spaceusefully employs the treated packaging materials, containers, and/orpackage inserts of the invention.

The surface area and thickness of the cured cyclodextrin compositionexposed to the interior of a produce container is selected to provide asuitable atmospheric (gaseous) concentration of the olefinic inhibitorto the enclosed space such that the useful life of the produce isoptimized. In many embodiments, optimum useful life of the produce meansextended for the maximum amount of time possible. The optimumatmospheric concentration of the olefinic inhibitor is dictated by thetype of produce to be packaged and the expected temperature of storageof the produce as well as the partial pressure of the olefinic inhibitorat the target temperature. Factors affecting the provision of theoptimum atmospheric concentration of olefinic inhibitor include theamount of cyclodextrin inclusion complex in the cyclodextrincomposition, the inherent equilibrium ratio of the cyclodextrininclusion complex with uncomplexed olefin inhibitor, the permeability ofthe cured cyclodextrin composition to the olefinic inhibitor, thepermeability of the packaging material to the olefinic inhibitor—thatis, the expected loss ratio of the olefinic inhibitor to the exterior ofthe package or container—the viscosity or coating thickness requirementsof the technique employed to coat the cyclodextrin composition, thevolume of the enclosed space surrounding the produce, and the amount ofwater expected within the container as a result of initial amountadded/enclosed and expected transpiration of the plant material. If thecontainer is not completely sealed to the exterior atmosphere, forexample if there are gaps or the packaging material itself has pores orholes, then any expected loss of released (gaseous) olefinic inhibitormust also be taken into account when calculating the amount ofcyclodextrin composition to be disposed in the interior of the producecontainer.

In embodiments, the amount of olefinic inhibitor in the atmosphere thatis required for a particular packaging application is estimated based onwhat produce is to be packaged and the known effective level of thatinhibitor with respect to the specific produce material; then thecoating thickness and area coated (that is, the total coating volume) isvaried based on the enclosed volume, and concentration of thecyclodextrin inclusion complex included in the cured cyclodextrincomposition. Other factors affecting olefinic inhibitor release from thecyclodextrin inclusion complex within a cured cyclodextrin compositionof the invention include the presence and amount of humectants ordesiccants within the package, water and 1-MCPpermeability/adsorbability/absorbability of the cured cyclodextrincomposition, water and 1-MCP permeability/adsorbability/absorbability ofthe packaging material, any controlled or modified atmosphere presentwithin the package, and respiration rate of the targeted producematerial. Further, the amount of water provided within the enclosedspace, that is, the amount of water vapor vs. liquid water in theenclosed space at the target temperature, must also be considered.

In such calculations, the value of delivering a targeted coating amountto the targeted enclosed volume is realized. Certain embodimentsdescribed above are particularly advantageous in delivering a preciselymeasured amount of olefinic inhibitor to an enclosed volume, as well asenabling an easily varied amount of cyclodextrin composition to a targetcontainer. For example, inkjet printing is well understood to deliverprecise and easily varied volumes of material to substrates over aneasily varied volume. Further, UV curable inkjet inks are known in theindustry and such apparatuses to apply and cure such inks are easilyobtained. We have found that UV curable inkjet formulations are easilymodified to include the small amount of the cyclodextrin inclusioncomplex necessary to accomplish delivery of the needed amount ofolefinic inhibitor to a surface of one or more packaging materials.Thus, in one embodiment of the invention, a UV curable inkjet ink ismodified to include an amount of a cyclodextrin inclusion complex, forexample by admixing the cyclodextrin inclusion complex into the ink; insome such embodiments, the ink is dried with a desiccant to remove waterbefore addition of the cyclodextrin inclusion complex. The modifiedinkjet ink thus obtained is delivered over a target area to thepackaging material and cured to provide a treated packaging material.Other printing techniques, for example flexographic printing, are alsoof utility in delivering a precise and reproducible amount ofcyclodextrin inclusion complex to a packaging material.

Another advantage of using printing techniques to deliver thecyclodextrin compositions of the invention is that printing is easilyincorporated into a production assembly line setup. Further, ink iseasily kept dry while in a tank awaiting printing on a production line.In this way, long term storage issues encountered in some applications,that is, the need to keep the cured cyclodextrin composition dry, isobviated. Yet another advantage of using printing techniques to applythe cyclodextrin compositions is the ability to employ reverse printlabeling. In reverse print labeling, a transparent labelstock is printedwith indicia on the side of the label that will contact the package,typically by virtue of an adhesive. Alphanumeric characters are thusprinted in reverse, that is, as the mirror images thereof. When thelabel is applied to the package, the labelstock protects the printedindicia from wear and tear. In the current use, the cyclodextrincomposition printed in reverse labeling mode is then disposed againstthe package or the produce. Reverse print labeling is also useful forprinting onto what will become the interior of a transparent package,such that the printed indicia is directly exposed to the interior of thepackage.

In some embodiments, delivering a targeted coating amount to thetargeted enclosed volume is realized by coating and curing acyclodextrin composition on a flat web, then cutting the web intoportions as treated package inserts. In some such embodiments, variablesize treated package inserts are cut to provide different amounts ofcyclodextrin inclusion complexes to address different producerequirements or different enclosed volumes. In other embodiments,uniform sections are cut and one, two, or more sections are included astreated package inserts in various packages depending on the type ofproduce and enclosed volume in each application. For example, inembodiments where the treated package insert is a label, one label isapplied to each produce item and several produce items are included in asingle enclosed space. Variable size containers holding a variablenumber of produce items is easily addressed in this manner.

In yet a different set of embodiments, the adhesive coated onto a labelis employed on the outside of a package to provide a packaging materialthat is a laminated packaging material.

In some embodiments, the packaging material used to make the treatedpackaging materials of the invention and the treated packages andcontainers of the invention employ further means to control the amountof water (vapor and/or liquid) enclosed within the treated package whilein the presence of the produce material. While the amount of water in apackage's enclosed space is of concern from the standpoint of release ofthe olefinic inhibitor from the cured cyclodextrin compositions of theinvention, it is well known that very high levels of moisture in apackage containing produce material is also separately detrimental tocertain moisture sensitive produce (berries, citrus, lettuce, mushrooms,onions, and peppers, for example). Excess moisture triggers variousphysiological disorders in some postharvest fruits and vegetables,shortening shelf life and quality. In particular, liquid water in theform of condensation on produce material surfaces hastens spoilage andconsiderably shortens storage life. In some embodiments, internalhumidity controllers (humectants and desiccants) are incorporated intoporous sachets, within the packaging material of the invention, or evenwithin the cyclodextrin compositions themselves in conjunction with thetreated packaging material of the invention. In embodiments, humiditycontrollers help maintain optimum in-package relative humidity (about85% to 95% for cut fruits and vegetables), reduce moisture loss from theproduce material itself, and/or prevent buildup of excess moisture inheadspace and interstices where microorganisms can grow. The amount of 1MCP incorporated within the packaging structure will be different inpackaging having excess water as contrasted by lower humidity packagingof low transpiration postharvest products. Therefore, to operate thetechnology a number of factors (chemical and biological) will beconsidered to manufacture optimum packaging structures and bulk shippingcontainers for different groups of postharvest products.

The treated packaging materials of the invention are also useful inembodiments where modified atmosphere packaging (MAP), equilibriummodified atmosphere packaging (EMAP), or controlled atmosphere packaging(CAP) is employed. The objective in MAP is to provide a desiredatmosphere around produce by providing a sealed container havingcontrolled permeability to oxygen and carbon dioxide, resulting in animprovement in produce quality when compared to air storage. Typically,the permeability of the container changes with temperature and partialpressures of each gas exterior to the container. The objective in CAP isto displace some or all of the atmospheric air composition (78% N₂, 21%O₂) within the container with e.g. carbon dioxide or nitrogen or a blendof two or more gases in a desired proportion. A number of patents setforth various features of MAP and CAP. U.S. Pat. No. 7,601,374 discussesboth approaches and also references a substantial list of other patentsissued for various MAP and CAP technologies. It will be appreciated thatthe cured cyclodextrin compositions of the invention find furtherutility in conjunction with MAP, CAP, or technologies that combinefeatures of both approaches.

MAP is a useful approach for maintaining improved flavored fruits andvegetables by minimizing development of off-flavors due to fermentativemetabolism or odor transfer from fungi or other sources. MAP isrecognized to improve resistance to postharvest stresses, decay andother plant disorders. An ‘active package’ having a modified atmosphereintegrated with the controlled release of an olefinic inhibitor asdelivered by the cyclodextrin compositions of the invention will improvethe quality of fresh-cut fruits and vegetables for consumers includingsingle-serve, ready-to-eat packaging and containers for vendingmachines. In an exemplary embodiment of the invention, MAP or CAP isused in conjunction with the treated packaging materials of theinvention for large polyethylene bags employed to packaging pallets ofcartons, wherein the cartons contain fresh produce. Such pallet-sizebags are widely employed for shipment of pallets of produce, supportedin cartons; the bags are employed for the purpose of enclosing theproduce in a modified or controlled atmosphere during shipping. In somesuch embodiments, the bags, the paperboard (e.g. polyethylene extrusioncoated paperboard) cartons, labels on the cartons or the bag, a treatedinsert, or a combination of two or more thereof include a treatedpackaging material of the invention.

EMAP is a method to help prolong the shelf life of fresh produce byoptimizing the in-package equilibrium atmosphere. This is achieved bymodifying the permeability of the packaging film. Film micro-perforationis one way to regulate the equilibrium concentrations of O₂ and CO₂.Micro-perforated films are apertured films or otherwise rendered porous,by puncturing or by stretching a film made from a mixture of athermoplastic material and particulate filler. These films permit thetransfer only by molecular gas/vapor diffusion and block the transfer ofliquid. Examples of microporous or micro-perforated films includeFRESHHOLD® film, available from River Ranch Technology, Inc. of Salinas,Calif.; P-PLUS® film, available from Sidlaw Packaging of Bristol, GreatBritain and described in U.S. Pat. Nos. 6,296,923 and 5,832,699; andfilms from Clopay Plastic Products Co. of Mason, Ohio described in U.S.Pat. Nos. 7,629,042 and 6,092,761.

Additionally, in some embodiments of the invention, the gas permeabilityof non-perforated and nonporous films is modified by simplymanufacturing films of different thicknesses or using the selectivity ofhydrophilic films produced from segmented block copolymers, andemploying these materials as packaging materials in conjunction with thecured cyclodextrin compositions. Segmented block copolymers ormulti-block copolymers consist of alternating flexible soft segments andcrystallizable rigid segments. The properties of segmented blockcopolymers are varied by changing the block lengths of the flexible(soft) and rigid segments. Rigid and flexible segments arethermodynamically immiscible and, therefore, phase separation occurs.The rigid segments crystallize and form lamellae in the continuous softphase. Rigid segments can contain ester, urethane or amide groups, whilethe flexible segments are usually polyesters or polyethers-poly(ethyleneoxide) (PEO) and/or more hydrophobic poly(tetramethylene oxide) (PTMO).In breathable film, the gas vapor is transported mainly through the softphase; selective gas permeability depends on the density of thehydrophilic groups in the polymer, the relative humidity, and thetemperature.

The treated packaging materials of the invention are also useful inembodiments where specialized and selectively permeable packagingmaterials are employed. One example of a selectively permeable packagingmaterial is BreatheWay® packaging, currently used in conjunction withfresh-cut produce marketed by Apio, Inc. of Guadalupe, Calif.BreatheWay® films are selectively permeable membranes that controlinflux of oxygen and outflux of carbon dioxide in order to provideadjusted O₂/CO₂ ratios to extend shelf life. The membranes are alsotemperature responsive. While such packaging provides improved O₂/CO₂ratios for extending shelf life of respiring produce, it does nototherwise inhibit ripening of the produce. Examples of other suitablebreathable hydrophilic films include PEBAX®, a thermoplastic polyamidemanufactured by Total Petrochemicals USA, Inc. of Houston, Tex.;SYMPATEX®, a breathable hydrophilic polyether-ester block copolymermanufactured by SympaTex Technologies GmbH of Unterfohring, Germany;HYTREL®, a thermoplastic polyester elastomer manufactured by DuPontdeNemours and Co. of Wilmington, Del.; and segmented polyurethanes suchas ELASTOLLAN® (ELASTOGRAN®) and PELLETHANE®, supplied by Dow Chemicalsof Midland, Mich. These polymers have a large, selective gaspermeability range. The cured cyclodextrin compositions of theinvention, in conjunction with such permeable membrane technology,represent a complete solution to extended shelf life of respiringproduce.

It will be appreciated that the end use articles and applications of theinvention benefit in a number of ways from the advantages offered by thecompositions and methods described herein. The cyclodextrin inclusioncomplexes are easily formed and isolated using mild conditions and highyields of inclusion complex formation are realized. The cyclodextrininclusion complexes are easily stored until added to a cyclodextrincomposition. The cyclodextrin compositions are easily formed, coated,and cured using mild conditions with generally small amounts of thecyclodextrin inclusion complex added to a curable and coatable orsprayable composition of easily varied viscosity. The cured cyclodextrincompositions are easily stored or can be formed and used in a productionline. A variable and precise amount of cyclodextrin inclusion complex iseasily and reproducibly added to produce packages. A variety of easilyimplemented methods of delivering the cured cyclodextrin compositions toproduce packages and packaging materials is possible.

4. 1-Methylcyclopropene (1-MCP) as the Olefinic Inhibitor

In embodiments where 1-MCP is the olefinic inhibitor, the targetconcentration for many produce items is between about 2.5 ppb to about10 ppm, or between about 25 ppb and 1 ppm. In embodiments the 1-MCPcyclodextrin inclusion complex is formed with α-cyclodextrin; that is,1-MCP/c/α-CD. A factor in addition to those factors mentioned aboveaffecting 1-MCP release from 1-MCP/c/α-CD is the amount of watercontained in the enclosed space. This requires consideration of theamount of water provided within the enclosed space, amount of waterreleased by respiring produce material, and the amount of water retainedwithin the package as that amount changes with plant respiration.

In embodiments of the invention where the cyclodextrin inclusion complex1-MCP/c/α-CD is employed in the cyclodextrin compositions, curedcyclodextrin compositions, treated packaging materials, and/or treatedcontainers of the invention, produce is packaged in the enclosed volumedefined by the container, and the treated packaging material is exposedto the interior atmosphere within the enclosed volume. Such exposure is,in various embodiments, either direct exposure of a cured coating withinthe interior atmosphere, or indirect exposure of such a coating appliedto the exterior of a package, wherein the package is permeable to water,1-MCP, or both. The enclosed volume includes an appropriate andactivating amount of water such that the 1-MCP/c/α-CD releases the 1-MCPinto the package interior at sufficient concentration to inhibit produceripening or maturation. The 1-MCP is also released from the packagingmaterial by exposing the packaging material to a controlled level ofwater vapor and/or liquid water. The release of 1-MCP from thecyclodextrin inclusion complex 1-MCP/c/α-CD facilitated by water vaporis explored and described in detail by Neoh, T. Z. et al., CarbohydrateResearch 345 (2010), 2085-2089. In embodiments, the cured cyclodextrincomposition is both permeable to the olefinic inhibitor and to watervapor to a sufficient degree to maintain a ripening or maturationinhibiting amount of olefinic inhibitor within the enclosed volume andin the presence of water vapor.

The researchers of Neoh, T. Z. et al., Carbohydrate Research 345 (2010),2085 2089 studied dynamic complex dissociation of 1-MCP/c/α-CD andobserved that increasing humidity generally triggered 1-MCP complexdissociation. However, the dissociation was greatly retarded at 80%relative humidity, presumably owing to collapse of the crystallinestructure; then abrupt dissociation corresponding to complex dissolutionwas observed at 90% relative humidity. However, the researchers noted,as did the inventors in this instant invention, that even at 100%relative humidity that less than 20% of the complexed 1-MCP is released.In fact, an average of less than one-fifth (˜17.6%) of the total amountof complexed 1-MCP was dissociated at the end of the experiments while˜83.4% 1-MCP remained complexed.

In some embodiments, during distribution and storage of the packagedproduce, when storage temperature is between about 0° C. and 20° C., therelative humidity in the enclosed volume around the produce will bebetween about 50% and 100% due to normal water loss from producerespiration within the enclosed package volume. The increase in humiditywithin the enclosed volume of the package is sufficient, in embodiments,to release a portion of the 1-MCP from the 1-MCP/c/α-CD. In otherembodiments, the internal humidity of the treated container is adjustedby the addition of water to the container prior to sealing to form theenclosed volume. In some such embodiments relative humidity within theenclosed volume is provided by adding moisture (water mist, spray orsteam) to air by humidifiers during packaging or by controlling thehumidity of the environment in the packaging location, within thepackage itself, or both.

Unexpectedly, the cured cyclodextrin compositions of the inventioncontinue to release higher concentrations of olefinic inhibitor withincreasing amounts of water, even as the amount of water in an enclosedspace reaches, and exceeds, the amount necessary to result in 100%relative humidity given the volume of space and the temperature. So forexample, in some embodiments, a package is formed from treated packagingmaterial; live plant material is added, and the package is sealed.Initially, the package contains less than 100% relative humidity; as theplant material respires within the package, 100% relative humidity isreached. As the humidity increases, the amount of olefinic inhibitorpresent in the atmosphere within the package also increases. In someembodiments, the amount of water released by the plant material exceedsthe amount constituting 100% relative humidity, such that liquid wateris formed. In such embodiments, we have found that the amount ofolefinic inhibitor released within the package continues to increaseeven though the amount of vapor phase water cannot be increased and onlyliquid water is released into the sealed package atmosphere. In ourexperiments, we have found that the levels of olefinic inhibitorreleased by the cured cyclodextrin compositions within an enclosed spacecontinues to increase in a predictable fashion with increasing amountsof water added, regardless of whether the water is in the form of vaporor liquid.

The relationship between the amount of water in an enclosed space andthe release of 1-MCP from 1-MCP/c/α-CD complex was very surprising whendissociation (release) of 1-MCP was measured as a function of wateraddition to the complex. Water solubility of α-CD is 14.5 grams/100 mL,or 14.5 wt-%, at typical ambient temperatures. As is reported in ControlExample A in the Experimental section below, a significant excess ofwater beyond the amount required to completely dissolve α-CD wasrequired to dissociate 100% of the 1-MCP from the complex. Therelationship between amount of water present and 1-MCP dissociation from1-MCP/c/α-CD has been demonstrated in a supplied complex alone, as wellas in the cured cyclodextrin compositions of the invention. Theimportance of the relationship between water and 1-MCP dissociation isof utmost importance in employing the technology because:

-   -   1) the amount of 1-MCP is regulated in the atmosphere        surrounding fruits and vegetables on a country-by-country basis;        and    -   2) the benefit (i.e., shelf life extension) derived from 1-MCP        differs with exposure concentration for various types of produce        material (see, e.g. Blankenship, S. M. and Dole, J. M.,        Postharvest Biology and Technology 28 (2003), 1-25); further,        adverse affects to some produce materials are possible with        excessive 1-MCP treatment concentrations.        In two examples of country-by-country regulation at the time of        this writing, the United States' Environmental Protection Agency        (EPA) currently limits 1-MCP to a maximum of 1 ppm in air by        authority of Section 408 of the Federal Food, Drug, and Cosmetic        Act (FFDCA); and the European Commission Health and Consumer        Protection Directorate and Member States of the European Food        Safety Authority similarly regulates 1-MCP under its various        directives, limiting 1-MCP levels to amounts ranging from 2.5        ppb v/v to 1 ppm v/v.

Thus, in embodiments, 1-MCP dissociation must be carefully managedwithin the package headspace by controlling both the total amount of1-MCP incorporated within the packaging structure and the release of1-MCP from the inclusion complex. Additionally, in embodiments, theamount of residual water inherently adsorbable or absorbable by thecured cyclodextrin compositions of the invention further affects 1 MCPdissociation. In embodiments, the hydrophilic nature of the cyclodextrinitself increases the compatibility of water with a cured cyclodextrincomposition into which a cyclodextrin inclusion complex is incorporated.

In embodiments of the invention where the cyclodextrin inclusion complexemployed in the treated packaging materials of the invention is1-MCP/c/α-CD, the amount of 1-MCP in the atmosphere that is required fora particular packaging application is calculated based on severalfactors; then the coating thickness and area coated (that is, the totalcoating volume) is varied based on the enclosed volume, concentration of1-MCP/c/α-CD included in the cured cyclodextrin composition, andapproximate fraction of 1-MCP/c/α-CD that is complexed (vs. uncomplexedα-CD) to arrive at the targeted atmosphere. Factors that must beconsidered in such a calculation include any humectants or desiccantswithin the package, water and 1-MCPpermeability/adsorbability/absorbability of the cured cyclodextrincomplex, water and 1-MCP permeability/adsorbability/absorbability of thepackaging material, any controlled or modified atmosphere present withinthe package, and respiration rate of the targeted produce material. Forexample, if an atmosphere containing 1 ppm of 1-MCP is required and thetargeted enclosed volume is 1 liter, then assuming 100% complexation andan overall density of the cured cyclodextrin composition of 1 g/cm³, acured cyclodextrin composition containing 1.71 wt % α-cyclodextrincoated 12.7 μm thick in an area totaling 2 cm² would provide thetargeted 1 ppm of 1-MCP to the enclosed volume in the presence of watervapor using Ideal Gas Law conversion. In embodiments, the targetedweight range of 1-MCP/c/α-CD is 25 micrograms to 1 milligram per 1 literof enclosed volume. In such calculations, the value of delivering atargeted coating amount to the targeted enclosed volume is realized.Certain embodiments described above are particularly advantageous indelivering a precisely measured amount of 1-MCP to an enclosed volume,as well as enabling an easily varied amount of cyclodextrin compositionto a target container. For example, in some embodiments, inkjet printingis well understood to deliver precise and easily varied volumes ofmaterial to substrates over an easily varied volume. In otherembodiments, addition of the inclusion complex to an adhesiveformulation onto a label, followed by cutting a precise size label toapply to a packaging material, results in delivery of a precise amountof 1-MCP/c/α-CD to the treated packaging material.

EXPERIMENTAL SECTION Example 1

A cyclodextrin inclusion complex is formed from α-cyclodextrin and1-methyl cyclopropene (1-MCP) using the technique described by Neoh, T.L. et al., J. Agric. Food Chem. 2007, 55, 11020-11026 “Kinetics ofMolecular Encapsulation of 1 Methylcyclopropene into α-Cyclodextrin.”The inclusion complex is termed “1-MCP/c/α-CD.” A 500 mL bottle ischarged with 97.0 g of isobornyl acrylate, 1.0 g of hexanedioldiacrylate, 1.0 g of 1-MCP/c/α-CD, and 1.0 g of 1-hydroxycyclohexylbenzophenone (IRGACURE® 184, obtained from Ciba Specialty ChemicalsCorp. of Tarrytown, N.Y.). The bottle is firmly capped and thecomponents are mixed by shaking the bottle briefly by hand.

About 2 mL of the mixture is removed with a metered dropper anddispensed on an 8.5 inch by nch PET film and drawn down using a meteringrod (Mayer rod) having a delivered coating thickness of 25 microns. Thenthe coated PET film is placed on a flat surface approximately 5 cmbeneath a medium pressure mercury arc lamp operating at 200 watts perinch (79 watts per cm). After 30 seconds under the lamp, the film isremoved. A silicone coated PET sheet (about 50 microns thick) is placedover the cured coating and allowed to sit on a laboratory benchovernight.

A die cutter is used to cut a 1 cm by 1 cm square of the coated portionof the sheet. The liner is removed from the coated square and the coatedsquare placed a 250 mL serum bottle. The bottle is then sealed with aTEFLON® faced silicone septa. Headspace concentrations of 1-MCP aremeasured after 1 hour following introduction of the coated square intobottle. The 1-MCP headspace concentration is quantified using gaschromatography by removing 1 mL of gas from the sample bottle using agas sampling valve interfaced directly to a GC column having FIDdetector. No measurable concentration of 1-MCP is detected because ofthe lack of humidity in the headspace of the jar.

Then 50 μL of deionized water is injected into the jar. Care is taken sothat the liquid water does not directly contact the coated square. Thesealed jar is allowed to sit on the lab bench for one hour after theinjection of water, then a second headspace sample is analyzed. A finalheadspace sample is analyzed 24 hours after the injection of water. At 1hour after injection of the water, 0.5 ppm of 1-MCP is measured in theheadspace. After 24 hours, 0.5 ppm of 1-MCP is measured in theheadspace.

Example 2

An inclusion complex of 1-butene and α-cyclodextrin was formed using thetechnique described by Neoh, T. L. et al., J. Agric. Food Chem. 2007,55, 11020-11026 “Kinetics of Molecular Encapsulation of1-Methylcyclopropene into α-Cyclodextrin” except that 1-butene (99.0%pure, Scott Specialty Gases, Plumsteadville, Pa.) was bubbled through asaturated a-cyclodextrin solution instead of 1-MCP. A precipitate wasformed during the process, which was collected by filtering through a 10micron fritted filter, and dried at ambient temperature at 0.1 mm Hg forabout 24 hours. The inclusion complex was termed “1-butene/c/α-CD.”

1-butene/c/α-CD was analyzed by adding 100 mg of the collected and driedprecipitate to a 250 mL glass bottle equipped with a septum cap, takingcare to ensure that no powder adheres to the walls of the bottle. Afterabout 1 hour, 250 μL of headspace gas was removed from the bottle usinga six port, two-position gas sampling valve (Valco #EC6W) interfaceddirectly to a gas chromatograph (GC; Hewlett Packard 5890) using a RTx-5GC column, 30 m×0.25 mm I.D., 0.25 μm film (obtained from Restek, Inc.,of Bellefonte, Pa.) and equipped with flame ionization detector (FID).No measurable concentration of 1-butene was detected because of the lackof humidity (water vapor) in the headspace of the bottle. Then 3 mL ofwater was injected into the bottle through the septum, and the bottle isplaced on a mechanical shaker and mixed vigorously for about 1 hour.After the shaking, 250 μL of the headspace gas is removed and added toan empty 250 mL bottle equipped with a septum cap, wherein the interiorof the bottle was purged with nitrogen gas. The headspace concentrationof 1-butene was quantified in the second bottle using gas chromatographyby removing 250 μL of gas from the 250 mL bottle using a six port,two-position gas sampling valve (Valco #EC6W) interfaced directly to aGC column having FID detector previously calibrated with a 6 point1-butene (99.0% pure, Scott Specialty Gases, Plumsteadville, Pa.)calibration curve. Employing this method, the yield of complexed1-butene/c/α-CD was found to be 72.5%.

A 20 mL bottle was charged with 9.8 g of UV Coating VP 10169/60 MF-2NE(obtained from Verga GmbH of Aschau am Inn, Germany) and 0.2 g of1-butene/c/α-CD. The bottle was firmly capped and the components weremixed by shaking the bottle by hand until uniformly dispersed.

About 3 mL of the mixture was removed with a dropper dispensed on aglass pan. A rubber ink roller was used to spread the mixture on theglass and roller. Next, the roller was used to coat the mixture on thecoated side of a 20 cm by 20 cm section of polyethylene extrusion coatedpaper (REYNOLDS® Freezer Paper, 90 microns total thickness). The rollerdelivered a coating nominal thickness of 0.3 microns. A razor blade wasused to cut a 5 cm by 10 cm rectangle from the coated sheet. Then thecoated cut rectangle was passed by hand about 10 cm beneath a mediumpressure mercury arc lamp operating at 200 watts per inch (79 watts percm). After 1.5 seconds exposure to the lamp, the cured rectangle wasremoved. The cured rectangle was allowed to sit on a laboratory benchovernight coating side down.

Six replicate coated rectangles were made in this fashion. Eachrectangle was placed in a 250 mL serum bottle. Then the six bottles weresealed with TEFLON® faced silicone septa. The 1-butene headspaceconcentration was quantified using gas chromatography by removing 250 μLof gas from the sample bottle using a six port, two-position gassampling valve interfaced directly to the GC column having FID detector.No measurable concentration of 1-butene was detected in the bottleheadspace.

Then 50 μL of deionized water was injected into each bottle. Care wastaken so that the liquid water did not directly contact the coatedrectangles. The headspace of each of the six sealed bottles was analyzedat 0.5, 1, 2, 4, 8, 24, and 96 hours after the injection of waterwherein about 3 mL of the 250 mL bottle headspace volume was removed foreach analysis. In each sampling, the amount of 1-butene released fromthe UV coated rectangles was quantified by gas chromatography against a6-point 1-butene calibration curve having a 0.998 correlationcoefficient. Table 1 and FIG. 1 illustrate the average of six replicatesamples of 1-butene headspace concentration and standard deviation.

TABLE 1 Headspace concentration of 1-butene according to the procedureof Example 2. 1-Butene Ave. ppm Stdev Hours (v/v) (ppm) 0.5 0.46 0.24 11.5 0.55 2 3.0 0.61 4 4.9 0.78 8 6.0 0.35 24 7.6 1.6 96 7.8 1.7

Example 3

A 20 mL bottle was charged with 9.6 g of UV Coating VP 10169/60 MF-2NE(obtained from Verga GmbH of Aschau am Inn, Germany). Then 0.4 g of1-MCP/a-cyclodextrin complex (4.7% 1-MCP obtained from AgroFresh ofSpring House, Pa.) termed “1-MCP/c/α-CD” was added to the bottle. Thebottle was then firmly capped and shaken by hand by hand until theblends appear uniformly dispersed, resulting in a 4.0 wt-% 1-MCP/c/α-CDblend. Three additional blends containing 2.0 wt-%, 1.0 wt-% and 0.5wt-% of 1-MCP/c/α-CD were prepared in the same manner.

A rubber ink roller was used to deliver a thin (nominally 0.3 μm)coating to a 20 cm by 20 cm polyethylene extrusion coated paper sheetusing the technique of Example 2.

Using razor blade, 2.5 cm×10 cm rectangles were cut from the coatedportion of each of the sheets. Then the coated rectangular sheets werecured using the procedure of Example 2. Each cured, coated rectangle wasplaced in a 250 mL serum bottle. The bottle was then sealed with TEFLON®faced silicone septa. Then 20 μL of deionized water was injected intoeach bottle. Care was taken so that the liquid water did not directlycontact the coated rectangles. Headspace was analyzed for 1-MCP 24 hoursafter the injection of water, using the technique employed in Example 2,and employing the 6 point 1-butene calibration curve as described inExample 2. Table 2 and FIG. 2 give the 24-hour average 1-MCP headspaceconcentration and standard deviation for each of the coated and curedrectangular sheets. These data illustrate that 1-MCP was released intothe headspace in a linear manner (0.99 correlation coefficient) withincreasing wt-% 1 MCP/c/α-CD in the coating when exposed to water vapor(humidity).

TABLE 2 Headspace concentration of 1-MCP according to the procedure ofExample 3. Wt-% 1-MCP 1-MCP/c/α- Ave. ppm Stdev CD (v/v) (ppm) 0.5 0.090.03 1 0.20 0.02 2 0.56 0.13 4 1.1 0.22

Example 4

A 4.0 wt-% 1-MCP/c/α-CD blend was made according to the technique ofExample 3. A rubber ink roller was used to deliver a coating having anominal thickness of 0.3 μm to a 20 cm by 20 cm polyethylene extrusioncoated paper sheet using the technique of Example 2. The coated sheetwas cured according to the procedure of Example 2.

Using a razor blade, 26 cm², 52 cm², and 78 cm² samples were cut fromthe coated portion of the sheet. Each sample was placed in a 250 mLserum bottle. The bottles were sealed with TEFLON® faced silicone septa.Then 20 μL of deionized water was injected into each bottle. Care wastaken so that the liquid water did not directly contact the test sample.Bottle headspace analysis was conducted according to the technique ofExample 3 at 0.17 hours, 0.5 hours, 1 hour, 2 hours, 4 hours and 24hours after the injection of water. 1-MCP headspace concentrations as afunction of test sample area and times are provided in Table 3 and FIG.3. These data illustrate that 1-MCP was released into the headspace in ain a predictable manner over time with increasing coated surface areahaving 4.0 wt-%1-MCP/c/α-CD when the coating is exposed to water vapor(humidity).

TABLE 3 Headspace concentration of 1-MCP according to the procedure ofExample 4. 26 cm² 52 cm² 78 cm² 1-MCP 1-MCP 1-MCP Time Hrs (ppm-v/v)(ppm-v/v) (ppm-v/v) 0.17 0.25 0.66 1.7 0.5 1.5 2.2 3.4 1 2.4 4.2 5.2 23.7 7.0 7.9 4 5.8 9.9 12.4 24 9.6 16.1 20.0

Example 5

Using a razor blade, six 5 cm×10 cm rectangles were cut from the coatedportions of 20 cm by 20 cm sheets prepared as in Example 3 and having1.0 wt-%, 2.0 wt-% and 4.0 wt-% 1-MCP/c/α-CD, and the coated rectangleswere cured according to the technique of Example 2. The rectangles wereindividually placed in 250 mL serum bottles. The bottles were sealedwith TEFLON® faced silicone septa. Then 20 μL of deionized water wasinjected into each bottle. Care was taken so that the liquid water didnot directly contact the test sample. Bottle headspace was analyzed at4, 8, 24 and 48 hours after the injection of water, using the techniqueof Example 3. The results are provided in Table 4 and FIG. 4 and givethe average headspace concentration and standard deviation for thedifferent wt-% 1-MCP/c/α-CD coatings as a function of time. These dataillustrate that 1-MCP was released into the headspace in a in apredictable manner over time with increasing wt-% 1-MCP/c/α-CD in thecoating when exposed to water vapor (humidity).

TABLE 4 Headspace concentration of 1-MCP according to the procedure ofExample 5. Wt-% 1-MCP/c/ 1-MCP (ppm- α-CD, v/v) in coated HoursHeadspace Stdev 1 4 0.96 0.15 1 8 2.0 0.44 1 24 3.6 0.98 1 48 4.0 1.2 24 3.5 1.2 2 8 7.8 2.6 2 24 17.8 5.9 2 48 21.2 7.5 4 4 7.5 0.08 4 8 13.51.3 4 24 24.0 1.8 4 48 28.0 0.05

Example 6

A 100 mL quartz beaker was charged with 54 g of 2-isooctyl acrylate, 6 gof acrylic acid, and 0.60 g of 1-hydroxycyclohexyl phenyl ketone(IRGACURE® 184, Ciba Specialty Chemicals Corp. of Tarrytown, N.Y.). Thebeaker was equipped with a mechanical stirrer, and the contents weremixed for about 5 minutes while sparging with dry helium. Then thebeaker was irradiated with a medium pressure mercury arc lamp operatingat 79 watts per cm situated about 15 cm from the side of the beaker. Thelight was turned off when the contents of the flask were of a honey-likeconsistency, about 1.5 minutes. The beaker was further charged with 3.23g of 1-MCP/c/α-CD, 0.89 g of IRGACURE® 184, 5.8 g of isooctyl acrylate,and 0.72 g of acrylic acid. The beaker contents were mixed untiluniformly dispersed, about 5 minutes.

About 4 mL of the mixture in the bottle was removed with a metereddropper and dispensed on 30.5 cm by 30.5 cm white paper labelstock, anddrawn down using a metering rod (Meyer coating rod #30) having adelivered coating thickness of 25 microns. Then a 21.5 cm by 28 cmsilicone coated polyester (PET) film sheet (120 μm thick (obtained fromthe 3M Company of St. Paul, Minn.) was placed over the coatedlabelstock, taking care not to entrain air bubbles. The coated andcovered labelstock was cut into 10 cm by 20 cm rectangles using a papercutter. The cut samples were passed by hand about 15 cm beneath a mediumpressure mercury arc lamp operating at 79 watts per cm; multiple handpasses beneath the UV light or about 30 seconds under the lamp was usedto cure the adhesive. The cured coated labelstock sheets were allowed tosit PET side up on a laboratory bench overnight.

A paper cutter was used to cut six replicate 2.5 cm by 2.5 cm squaresfrom the sheets. Because the UV cured coating composition is a pressuresensitive adhesive, or PSA, the 2.5 cm by 2.5 cm squares are termed “PSAlabels.” Each PSA label, with the silicone coated PET still in place,was placed in a 250 mL serum bottle. Each bottle was sealed with aTEFLON® faced silicone septum. The headspace concentration of 1-MCP wasmeasured after 1 hour following introduction of the PSA label into abottle, using the technique of Example 3 except that 250 μL of gas wasremoved from the sample bottle for the analysis. 1-MCP was below thequantification limit of 0.01 ppm.

Then 50 μL of deionized water was injected into each bottle. Care wastaken so that the liquid water did not directly contact the labels. Thesealed bottle headspace was analyzed at 10 minutes, 30 minutes, and 60minutes, using the technique of Example 3. A final headspace sample wasanalyzed 16 hours after the injection of water. These data are shown inTable 5. The data illustrate that 1-MCP was released from a PSA labelinto the headspace when exposed to water vapor (humidity) and that itsconcentration increases over time.

TABLE 5 Headspace concentration of 1-MCP according to the procedure ofExample 6. 1-MCP ppm (v/v) Hours Average Stdev 0.17 0.01 0.01 0.5 1.30.84 1 3.6 0.75 16 29.7 8.0

Example 7

This method is designed to measure the permeability of 1-MCP throughpolyethylene film into a confined, fixed volume headspace followingrelease from a PSA label adhered to the surface of the film defining thefixed volume. The methodology simulates the headspace of a flexible filmpackage having initially low relative humidity, wherein a PSA labelcontaining 1-MCP is adhered to the outside of the package. As thehumidity rises inside the package by respiration of fresh agriculturalproducts, the water vapor increases in concentration and it diffusesthrough the package film to the outside environment but also into thePSA. Thus, as the water vapor diffuses through the film into the 1-MCPadhesive label adhered to the outside of the package film; 1-MCPreleased from the label adhesive into the fixed volume (headspace) wasmeasured.

A coated, cured labelstock sheet made according to the procedure ofExample 6 was cut by hand into an 11 cm diameter circle. Next the PETliner was removed from the label and the label was adhered via the PSAto a 13.5 cm diameter, 1 mil (25 μm) thick polyethylene (PE) film(obtained from the Pliant Corporation of Schaumburg, Ill.). The paperside of this structure was then covered with aluminum foil. Thefoil/paper/PSA/PE layered structure was mounted onto the open end of a1,000 mL glass reaction kettle bottom (6947-1LBO, from Corning Glass ofCorning, N.Y.) and sealed to the kettle's glass flange using aluminumsealing rings. The layered structure was oriented over the 11 cm openingwith the PE film facing in and the aluminum facing out. The glassreaction kettle was modified with a silicone septum port to allowsampling of the 1,000 mL headspace. Headspace analysis was conducted byremoving 250 μL of headspace volume from the 1,000 mL glass kettle andanalyzing according to the technique of Example 3.

Two hours after the film and label were sealed to the flange of thereaction kettle bottom and without any added water inside the 1,000 mLvolume; an initial headspace analysis was conducted and revealed nodetectible levels of 1-MCP (<0.01 ppm). Then 200 μL of water was addedthrough the septum port to the inside of the glass kettle. The headspacewas analyzed for 1-MCP at 17, 25 and 90 hours after the injection ofwater using the technique employed in Example 3. At 17 hours, 25 hours,and 90 hours after injection of the water, the 1-MCP headspaceconcentration was 3.6 ppm, 7.0 ppm and 8.0 ppm of 1-MCP, respectively.These results demonstrate a PSA coated label containing 1 MCP andadhered to a vapor permeable film surface can release 1-MCP to theinside package headspace following the introduction of water vaporinside the package headspace.

Control Example A

Water solubility of a-CD is 14.5 grams/100 mL, or 14.5 wt-%, at typicalambient temperatures (Szejtli, J. (1988), Cyclodextrin Technology,Kluwer Academic Publishers, page 12). A sample of 1-MCP/c/α-CD powderwas obtained (AgroFresh of Spring House, Pa.). According to thesupplier's specification sheet, 1-MCP was 4.7 wt % of α-CD or 88.7 wt %1-MCP complex based on a theoretical 1:1 molar ratio of 1-MCP to α-CD;this corresponds to a resulting headspace concentration of 8,600 ppm. Aseries of tests were conducted to measure the dissociation of 1-MCP fromthe supplied 1-MCP/c/α-CD as a function of added water. First, 0.1 galiquots of the supplied 1-MCP/c/α-CD powder were added to each of 5,250 mL bottles, which were then capped with TEFLON® faced septa. Varyingamounts of water were added to the bottles by syringe, and then thebottles were mechanically shaken for one hour, followed by headspacemeasurement for 1-MCP according to the procedure of Example 3. Theamounts of water added per 0.1 g of the supplied 1-MCP/c/α-CD complex,and the resulting headspace measurements after 1 hour at about 20° C.,are shown in Table 6.

Our test results showed a 5.8 wt % 1-MCP or 111 wt % 1-MCP/c/α-CDcomplex (greater than 1:1 complex) resulting in a headspaceconcentration of 10,610 ppm. At 1.0 grams of water per 0.10 grams1-MCP/c/α-CD, a-CD water solubility was exceeded yet 1-MCP was only 66%dissociated. A polynomial regression was used to calculate thedissociation at 100% RH in the headspace for the five samples of Table 6(i.e., 4.3 milligrams water per 250 mL volume, see Example 8 for sourceand calculation of this information). The calculated amount ofdissociated 1-MCP at 100% RH was 18 wt-%.

These results were surprising since a significant excess of water beyondthe amount required to completely dissolve a-CD (14.5 grams/100 mL, asreported above) was required to dissociate 100% of the complexed 1-MCP.

TABLE 6 Headspace concentration of 1-MCP according to the procedure ofControl Example A. 1-MCP, ppm H₂O, g (v/v) 0.25 3,050 0.5 4,750 1.06,850 2.0 9,850 3.0 10,610

Example 8

A 4.0 wt-% 1-MCP/c/α-CD coating blend was made according to thetechnique of Example 3. A 20 cm by 20 cm polyethylene extrusion coatedpaper sheet was coated with the mixture using the technique of Example2. A paper cutter was used to cut nine, 5 cm by 10 cm rectangles fromthe sheet. The cut, coated rectangles were passed by hand about 10 cmbeneath a medium pressure mercury arc lamp operating at 79 watts per cm.After 1.5 seconds exposure to the lamp, the sample was removed. Thecured sample was allowed to sit on a laboratory bench overnight coatingside down.

Each cured sample was placed in a 250 mL serum bottle. Each bottle wassealed with a TEFLON® faced silicone septum. The amount of liquid waterthat would, in vapor form, correspond to 100% relative humidity (RH) at20° C. is 17.3 g/m³, or 17.3 g per 1000 L. The density of water at 20°C. is 0.9982 g/mL. Thus, at 20° C., 4.3 μL of liquid water added to anenclosed volume of 250 mL and containing no other water will vaporize togive 100% RH. Our laboratory facility temperature was 20° C.±5° C.

Three of the bottles were injected with 10 μL of deionized water, threewith 20 μL of deionized water, and three with 50 μL of deionized water.Care was taken so that the liquid water did not directly contact thecoated square. The headspace of each bottle was analyzed for 1-MCP at 2hours, 4 hours, 8 hours, 24 hours, and 48 hours after the injection ofwater, wherein the headspace analysis was conducted using the analyticaltechnique employed in Example 3. The results of average headspaceconcentration and standard deviation are provided in Table 7 and FIG. 5.

TABLE 7 Headspace concentration of 1-MCP according to the procedure ofExample 8. 1-MCP, average, H₂0, Time, ppm μL hr (v/v) Stdev 10 2 1.30.77 10 4 2.5 0.81 10 8 3.8 0.94 10 24 7.1 1.5 10 48 10.0 2.0 20 2 2.61.1 20 4 5.8 1.3 20 8 9.2 1.7 20 24 15.7 1.9 20 48 20.5 2.0 50 2 8.7 4.150 4 18.6 3.6 50 8 30.8 0.42 50 24 55.3 10.7 50 48 63.0 17.0

Example 9

UV curable ink designed for thermal inkjet cartridges and industrialprinting was formulated with 1-MCP/c/α-CD and printed onto film todemonstrate how UV ink can be incorporated into a flexible-packagestructure to release 1-MCP. ImTech UVBLK Series 912 cartridges wereobtained from ImTech Inc. of Corvallis, Oreg. About 40 g of black inkwas removed from the cartridge in which the ink was supplied. The inkwas dried overnight in a closed container with 3A molecular sieves toremove residual water contained in the ink. Then 17.5 g of the dried inkwas transferred to a 70 mL roller mill jar filled with 50 g of 3 mmglass beads to which 0.875 g of 1-MCP/c/α-CD was added to the UV ink.The jar was sealed and rotated on a roller mill at 140 rpm for fourhours. At the end of four hours of rolling to disperse the 1-MCP/c/α-CD,an additional 4.375 g of dry UV ink was added making a 4 wt-%1-MCP/c/α-CD containing ink. Then the ink was decanted from the glassbeads.

A rubber ink roller was used to coat a discontinuous, thin (nominally 3μm), but uniform UV ink coating onto a 10 cm by 20 cm section of PETfilm (120 microns thick, obtained from the 3M Company of St. Paul,Minn.) in the manner described in Example 2. UV ink coated rectangleswere passed by hand about 10 cm beneath a medium pressure mercury arclamp operating at 79 watts per cm for 1.5 seconds exposure to the lamp.The cured sample was allowed to sit on a laboratory bench overnight inkside down.

A paper cutter was used to cut two samples, 20 cm² and 81 cm², from thecured ink coated PET film sheet. The samples were individually placed in250 mL serum bottles. The bottles were then sealed with TEFLON® facedsilicone septa. Then 200 μL of deionized water was injected into thebottle. Care was taken so that the liquid water did not directly contactthe ink coated PET film. After the injection of water into the bottle,1-MCP was measured in the headspace using the analytical techniqueemployed in Example 3. The test results are tabulated in Table 8; theresults demonstrate 1-MCP release from the UV ink. The results furtherdemonstrate that the 1-MCP releases slowly, increasing the bottleheadspace concentration with increasing time.

TABLE 8 Headspace concentration of 1-MCP according to the procedure ofExample 9. 20 cm² 81 cm² 1-MCP ppm 1-MCP ppm Hours (v/v) (v/v) 0.17 NDND 0.5 <0.01 <0.01 1 <0.01 0.05 2 0.01 0.18 4 0.04 — 8 0.05 — 21 — 0.5127 0.09 — 48 — 0.60 170 0.76 —

Example 10

The ink containing 4 wt-% 1-MCP/c/α-CD from Example 9 was loaded backinto the previously emptied cartridge. After refilling the cartridge, itwas installed into a HP Inkjet 1600C printer (obtained from theHewlett-Packard Company of Palo Alto, Calif.) and the calibration orhead cleaning function was run. A medium density, black cross-hatchpattern obtained from Microsoft EXCEL software program 2003 (obtainedfrom the Microsoft Corporation of Redman, Wash.) was used to format theentire printable page. The EXCEL pattern image was printed onto 3M,CG3460 Transparency Film (polyester film 120 microns thick for HP inkjetprinters; obtained from the 3M Company of St. Paul, Minn.) using thedried, milled ink containing 4 wt-% 1-MCP/c/α-CD of Example 9.Immediately after printing, the printed side of the transparency filmwas overlaid with a 25 μm polyethylene film and then passed by handabout 10 cm beneath a medium pressure mercury arc lamp operating at 79watts per cm for 3 seconds exposure to the lamp, with the polyethyleneside facing the lamp. The methodology simulates a multilayerflexible-package where the inner surface of an outer, transparent, layerof the multilayer flexible material was printed (referred to as reverseprinting). The printed surface was then laminated to other layers. Theoutside layer itself serves to protect the ink from abuse.

The following technique was designed to measure the permeability of1-MCP, which was released from the reverse inkjet printed 3MTransparency Film, through PE film as the “inner layer” of a multilayerproduce package. In a multilayer produce package, as the humidity risesinside the package by respiration of fresh agricultural products, thewater vapor reaches a concentration that allows it to diffuse to theoutside of the package. In this example, water also diffuses through theink layer containing 1-MCP/c/α-CD. The reverse printed ink on the PETfilm releases 1-MCP which diffuses through the PE film into the interiorof package (headspace) under a gradient of low 1-MCP concentrationinside the bottle headspace and high 1-MCP concentration within themultilayer structure.

Using a paper cutter, a 5.5 cm by 16 cm rectangle (88 cm²) was cut fromthe multilayer structure of the printed, cured ink on the PET sheetoverlaid with PE. The rectangle was placed in a 250 mL serum bottle. Thebottle was then sealed with a TEFLON® faced silicone septa. Then 100 μLof deionized water was injected into the bottle. Care was taken so thatthe liquid water did not directly contact the test sample. Bottleheadspace was analyzed at 0.17, 0.5, 1, 2, 4, and 24 hours after theinjection of water using the technique employed in Example 3. Theresults in Table 8 illustrate 1 MCP headspace concentration as afunction of time for the “multilayer” film.

A second piece of PET transparency film was printed as in Example 9except that the transparency film was not covered with PE film; theprinted ImTech UVBLK Series 912 ink was cured on the PET film surfaceusing a medium pressure mercury arc lamp operating at 79 watts per cm inthe same manner as for Example 9. Then, using a paper cutter, a 1.2 cmby 16 cm rectangle (19 cm²) was cut from the sheet. The rectangle wasplaced in 250 mL serum bottle. The bottle was then sealed with a TEFLON®faced silicone septa. Then 100 μL of deionized water was injected intothe bottle. Care was taken so that the liquid water did not directlycontact the test sample. Bottle headspace was analyzed at 0.17, 0.5, 1,2, 4, and 24 hours after the injection of water using the techniqueemployed in Example 3. The headspace concentration of 1-MCP as afunction of time is also reported in Table 9 for the “monolayer” film.

TABLE 9 Headspace concentration of 1-MCP according to the procedure ofExample 10. 88 cm² 19 cm² Multilayer Monolayer 1-MCP ppm 1-MCP ppm Hours(v/v) (v/v) 0.17 0.25 0.50 0.5 0.46 0.52 1 1.1 0.50 2 1.5 0.51 4 3.20.52 24 8.3 0.49

Example 11

Polyethylene extrusion coated paperboard is one of the most commonlyused fresh produce packaging materials. Typically, the paperboard isrecyclable and has a thin (generally 30 μm or less) layer ofpolyethylene on one side or both sides. The extrusion coated surface canbe coated or printed with a UV curable coating containing 1-MCP.

A 20 mL bottle was charged with 9.6 g of UV curable coating formulation(VP 10169/60 MF-2NE, obtained from Verga GmbH of Aschau am Inn,Germany). Then 0.4 g of 1-MCP/c/α-CD (4.7% 1-MCP, obtained fromAgroFresh of School House, Pa.) was added to the bottle. The bottle wasfirmly capped and the components mixed by shaking the bottle by handuntil the contents appeared to be uniformly dispersed, providing a UVcurable mixture.

A polyethylene coated paperboard was prepared by heat laminating a 30 μmthick polyethylene film to a 20 cm×20 cm section of 600 μm thick solidbleached sulfate (SBS) paperboard (obtained from Graphic PackagingInternational of _) using a heated vacuum press. A rubber ink roller wasused to deliver a thin (nominally 0.3 μm) coating of the UV curablemixture to the laboratory prepared polyethylene coated paperboard, usingthe technique of Example 2. A paper cutter was used to cut a 20 cm by 10cm rectangle of the coated portion of the board. The coated rectanglewas passed by hand about 10 cm beneath a medium pressure mercury arclamp operating at 79 watts per cm. After 1.5 seconds exposure to thelamp, the sample was removed. The cured sample was allowed to sit on alaboratory bench overnight, coating side down.

After curing, 5 cm by 5 cm sections were cut from the 20 cm by 10 cmrectangles. Each section was individually placed into a 250 mL jar (tallclear WM SEPTA-JAR™, Fisher Scientific P/N 05-719-452; obtained fromFisher Scientific of Waltham, Mass.) equipped with a TEFLON™ facedseptum (Fisher Scientific P/N 14-965-84). Each jar was injected with 200μL of deionized water. Care was taken so that the liquid water did notdirectly contact the coated square. Jar headspace was analyzed for 1-MCPat five time periods (0.0.17, 0.5, 1, 2, 4 and 7 hours) after theinjection of water, using the analytical technique employed in Example3. The average headspace concentration of 1-MCP and standard deviationare tabulated in Table 10. The results exemplify that greater amounts of1-MCP were released into the headspace from the UV coated substrate withincreasing time.

TABLE 10 Headspace concentration of 1-MCP according to the procedure ofExample 11. 1-MCP ppm Hours (v/v) Stdev 0.17 0.16 0.09 0.5 0.63 0.40 11.6 0.67 2 3.6 1.5 4 7.3 2.5 7 12.5 2.8

REPRESENTATIVE EMBODIMENTS

We now recite certain representative embodiments of the invention. Theinvention is not limited to these embodiments and other embodimentsdescribed above are also embodiments of the invention, or areembodiments of the invention when combined with any combination of theembodiments described below.

Embodiment 1

Embodiment 1 is suitably an embodiment of the invention either alone orwhen further combined with any additional limitation or element asdescribed either above or in the following list. Embodiment 1 can becombined with a combination of two or more additional limitations orelements described above or in the following list. The following listcontains limitations or elements that are intended to be combined in anymanner with Embodiment 1 as further aspects of the invention, includingin combination with any one or more other limitations or elementsdescribed above.

Embodiment 1 of the invention is a cyclodextrin composition comprisingone or more radiation polymerizable monomers and a cyclodextrininclusion complex, the cyclodextrin inclusion complex comprising acyclodextrin compound and an olefinic inhibitor of an ethylenegeneration in produce, the olefinic inhibitor comprising a compoundhaving the structure

wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup and R³ and R⁴ are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup with the proviso that at least one of R¹ or R² is methyl.

The list of additional limitations or elements includes, but is notlimited to, the following:

-   -   a. the one or more radiation polymerizable monomers comprise        acrylic acid, methacrylic acid, an acrylate ester, a        methacrylate ester, an acrylamide, a diacrylate, a triacrylate,        a tetraacrylate, or a mixture thereof;    -   b. the acrylate or methacrylate ester is an ester of an alcohol        having between 1 and 18 carbons and is a linear, branched, or        cyclic ester;    -   c. the composition further comprises a photoinitiator;    -   d. the composition further comprises one or more prepolymers;    -   e. the cyclodextrin comprises a cyclodextrin derivative;    -   f. the cyclodextrin inclusion complex contains about 0.1 to 0.99        mole of olefinic inhibitor per mole of cyclodextrin;    -   g. the olefinic inhibitor comprises 1-methyl cyclopropene;    -   h. the cyclodextrin comprises α-cyclodextrin;    -   i. the cyclodextrin inclusion complex contains about 0.80 to        0.99 mole of 1-methyl cyclopropene per mole of α-cyclodextrin;    -   j. the composition comprises between 0.01 wt % and 10 wt % of        the cyclodextrin inclusion complex based on the weight of the        composition;    -   k. the composition is coatable;    -   l. the composition is printable;    -   m. the composition is an ink;    -   n. the composition is a UV curable ink;    -   o. the composition further comprises one or more colorants;    -   p. the composition further comprises one or more adhesion        promoters, antifouling agents, thermal stabilizers, oxidative        stabilizers, water scavengers, adjuvants, plasticizers, or a        combination of two or more thereof;    -   q. the composition further comprises one or more desiccants;    -   r. the composition further comprises one or more desiccants        comprising silica gel, molecular sieves, or a combination        thereof.

Embodiment 2

Embodiment 2 is suitably an embodiment of the invention either alone orwhen further combined with any additional limitation or element asdescribed either above or in the following list. Embodiment 2 can becombined with a combination of two or more additional limitations orelements described above or in the following list. The following listcontains limitations or elements that are intended to be combined in anymanner with Embodiment 2 as further aspects of the invention, includingin combination with any one or more other limitations or elementsdescribed above.

Embodiment 2 of the invention is a treated packaging material comprisinga packaging material and a cured cyclodextrin composition disposed on atleast a portion of one surface of the packaging material, the curedcyclodextrin composition comprising a polymer derived from one or moreradiation polymerizable monomers and a cyclodextrin inclusion complex,the cyclodextrin inclusion complex comprising cyclodextrin and anolefinic inhibitor of an ethylene generation in produce, the olefinicinhibitor comprising a compound having the structure

wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup and R³ and R⁴ are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup with the proviso that at least one of R¹ or R² is methyl.

The list of additional limitations or elements includes, but is notlimited to, the following:

-   -   a. the treated packaging material comprises a film, a sheet, a        foil, a bag, a punnett, a dish, a cup, a cover, a label,        paperboard, a paperboard carton, or a treated package insert;    -   b. the packaging material comprises a polyolefin or a polyester;    -   c. the surface comprises a plasma treated surface;    -   d. the treated packaging material further comprises a primer        disposed between the packaging material and the cured        cyclodextrin composition    -   e. the cured cyclodextrin composition is permeable to water and        to the olefinic inhibitor;    -   f. the cured cyclodextrin composition has differential        permeability to water and the olefinic inhibitor;    -   g. the treated packaging material comprises a film, a sheet, a        treated package insert, or a label and further comprising a        liner disposed on top of the cured cyclodextrin composition;    -   h. the liner is transparent to UV light;    -   i. the liner is a foil;    -   j. the liner further comprises one or more desiccants;    -   k. the liner is preferentially removable at the interface of the        liner and the cured cyclodextrin composition;    -   l. the liner is impermeable to water;    -   m. the packaging material is impermeable to water;    -   n. the packaging material is impermeable to the olefinic        inhibitor;    -   o. the packaging material is permeable to water, permeable to        the olefinic inhibitor, or permeable to both water and the        olefinic inhibitor    -   p. the packaging material is a selectively permeable membrane;    -   q. the cured cyclodextrin composition comprises a pressure        sensitive adhesive;    -   r. the cured cyclodextrin composition is present as a coating on        the packaging material;    -   s. the coating is about 0.01 micron to 1 millimeter thick;    -   t. the coating comprises printed indicia;    -   u. the cured cyclodextrin composition is bonded to the packaging        material;    -   v. the packaging material comprises a treated laminate;    -   w. the packaging material comprises a treated laminate that is        permeable to the olefinic inhibitor on a first side thereof and        is impermeable to the olefinic inhibitor on a second side        thereof;    -   x. the packaging material comprises a treated laminate that is        permeable to water on at least a first side thereof;    -   y. the treated packaging material is tentered.

Embodiment 3

Embodiment 3 is suitably an embodiment of the invention either alone orwhen further combined with any additional limitation or element asdescribed either above or in the following list. Embodiment 3 can becombined with a combination of two or more additional limitations orelements described above or in the following list. The following listcontains limitations or elements that are intended to be combined in anymanner with Embodiment 3 as further aspects of the invention, includingin combination with any one or more other limitations or elementsdescribed above.

Embodiment 3 of the invention is a container comprising a treatedpackaging material, wherein the container comprises an enclosed volume,the treated packaging material comprising a cured cyclodextrincomposition disposed on at least a portion of a surface of a packagingmaterial, the cured cyclodextrin composition comprising a polymerderived from one or more radiation polymerizable monomers and acyclodextrin inclusion complex, the cyclodextrin inclusion complexcomprising an olefinic inhibitor of an ethylene generation in produce,the olefinic inhibitor comprising a compound having the structure

wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup and R³ and R⁴ are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup with the proviso that at least one of R¹ or R² is methyl.

The list of additional limitation or elements includes, but is notlimited to, the following:

-   -   a. the container is a bag, a punnett, a dish, a cup, or a        paperboard carton;    -   b. the cured cyclodextrin composition is present as a coating on        at least a portion of an interior surface of the container;    -   c. the cured cyclodextrin composition is present as a coating on        at least a portion of an exterior surface of the container;    -   d. the cured cyclodextrin composition is present as a coating on        a package insert;    -   e. the container is a treated laminated container;    -   f. the container is a treated laminated container wherein the        laminate structure is permeable to the olefinic inhibitor on a        first side thereof and is impermeable to the olefinic inhibitor        on a second side thereof;    -   g. the container is a treated laminated container wherein the        laminate structure is permeable to water on at least a first        side thereof;    -   h. the container further comprises a desiccant;    -   i. the container further comprises an item of produce;    -   j. the enclosed volume comprises between 50% relative humidity        and 100% relative humidity at a temperature between about 0° C.        and 20° C.;    -   k. the enclosed volume comprises 100% relative humidity at a        temperature between about 0° C. and 20° C. and further comprises        liquid water;    -   l. the container comprises a modified atmosphere package;    -   m. the container comprises a controlled atmosphere package    -   n. the container comprises a selectively permeable membrane;    -   o. the olefinic inhibitor is present in the enclosed volume at a        concentration of about 2.5 parts per billion to 10 parts per        million;    -   p. the olefinic inhibitor is present in the enclosed volume at a        concentration of about 25 parts per billion to 1 part per        million.

Embodiment 4

Embodiment 4 is suitably an embodiment of the invention either alone orwhen further combined with any additional limitation or element asdescribed either above or in the following list. Embodiment 4 can becombined with a combination of two or more additional limitations orelements described above or in the following list. The following listcontains limitations or elements that are intended to be combined in anymanner with Embodiment 4 as further aspects of the invention, includingin combination with any one or more other limitations or elementsdescribed above.

Embodiment 4 of the invention is a method of making a treated packagingmaterial, the method comprising

-   -   forming a cyclodextrin composition comprising one or more        radiation polymerizable monomers and about 0.05 wt % to 10 wt %        of a cyclodextrin inclusion complex based on the weight of the        cyclodextrin composition, the cyclodextrin inclusion complex        comprising cyclodextrin and an olefinic inhibitor of an ethylene        generation in produce, the olefinic inhibitor comprising a        compound having the structure

-   -   wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆        hydrocarbyl group and R³ and R⁴ are independently hydrogen or a        C₁₋₁₆ hydrocarbyl group with the proviso that at least one of R¹        or R² is methyl;    -   disposing the cyclodextrin composition onto at least a portion        of one surface of a packaging material at a thickness of about        0.01 micron to 1 millimeter to form a coating; and    -   exposing the coating to a source of radiation to form a cured        cyclodextrin composition.

The list of additional limitations or elements includes, but is notlimited to, the following:

-   -   a. the cyclodextrin composition further comprises about 0.1 wt %        to 5 wt % of one or more photoinitiators based on the weight of        the composition, wherein the irradiating is accomplished with UV        radiation;    -   b. the cyclodextrin composition further comprises about 0.1 wt %        to 5 wt % of one or more photoinitiators based on the weight of        the composition; and further comprising an additional exposing        of the cyclodextrin composition to a source of radiation prior        to coating, wherein the source of radiation is ultraviolet        radiation;    -   c. one or more additional monomers, an additional        photoinitiator, or a combination thereof is added to the        cyclodextrin composition after the additional exposing and        before the disposing;    -   d. the source of radiation is electron beam radiation;    -   e. the source of radiation is ultraviolet radiation;    -   f. the coating is disposed over the entirety of one major        surface of the packaging material;    -   g. the coating is disposed on a portion of one major surface of        the packaging material;    -   h. the disposing is accomplished by printing;    -   i. the printing is gravure printing, flexographic printing, or        inkjet printing;    -   j. the cured cyclodextrin composition comprises a pressure        sensitive adhesive;    -   k. a liner is disposed over the cyclodextrin composition;    -   l. the liner is disposed prior to irradiating;    -   m. the liner is disposed after irradiating;    -   n. the liner comprises a desiccant;    -   o. the treated packaging material is a treated container;    -   p. the method further comprises forming a treated container from        the treated packaging material;    -   q. the method further comprises forming a treated package insert        from the treated packaging material;    -   r. the method further comprises forming a treated label from the        treated packaging material;    -   s. the method further comprises forming a treated laminate;    -   t. the method further comprises forming a treated laminated        container;    -   u. the method further comprises disposing the cured cyclodextrin        composition inside a container having an enclosed volume,        wherein the cured cyclodextrin composition contacts the enclosed        volume;    -   v. the method further comprises disposing the cured cyclodextrin        composition on the outside of a container having an enclosed        volume, wherein the cured cyclodextrin composition is not in        direct contact with the enclosed volume;    -   w. the method further comprises enclosing an item of produce        inside the container.

The foregoing discloses embodiments of the invention. In the descriptionand claims, “about” modifying, for example, the quantity of aningredient in a composition, concentration, volume, process temperature,process time, yield, flow rate, pressure, and like values, and rangesthereof, employed in describing the embodiments of the disclosure,refers to variation in the numerical quantity that can occur, forexample, through typical measuring and handling procedures used formaking compounds, compositions, concentrates or use formulations;through inadvertent error in these procedures; through differences inthe manufacture, source, or purity of starting materials or ingredientsused to carry out the methods, and like proximate considerations. Theterm “about” also encompasses amounts that differ due to aging of aformulation with a particular initial concentration or mixture, andamounts that differ due to mixing or processing a formulation with aparticular initial concentration or mixture. Where modified by the term“about” the claims appended hereto include equivalents to thesequantities. “Optional” or “optionally” means that the subsequentlydescribed event or circumstance may but need not occur, and that thedescription includes instances where the event or circumstance occursand instances in which it does not. The present invention may suitablycomprise, consist of, or consist essentially of, any of the disclosed orrecited elements. Thus, the invention illustratively disclosed hereincan be suitably practiced in the absence of any element which is notspecifically disclosed herein. The use of the singular typicallyincludes and at least does not exclude the plural.

The specification, figures, examples and data provide a detailedexplanation of the invention as it has been developed to date. Theinvention, however, can take the form of other embodiments withoutdeparting from the spirit or the intended scope of the invention. Theinvention therefore resides in the appended claims.

What is claimed is:
 1. A method of making a treated packaging material,the method comprising a. forming a cyclodextrin composition comprisingone or more radiation polymerizable monomers and about 0.05 wt % to 10wt % of a cyclodextrin inclusion complex based on the weight of thecyclodextrin composition, the cyclodextrin inclusion complex comprisingcyclodextrin and an olefinic inhibitor compound having the structure

wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup and R³ and R⁴ are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup with the proviso that at least one of R¹ or R² is methyl; b.disposing the cyclodextrin composition onto at least a portion of onesurface of a packaging material at a thickness of about 0.01 micron to 1millimeter to form a coating; and c. exposing the coating to electronbeam radiation to form a treated packaging material.
 2. The method ofclaim 1 wherein the thickness of the disposing is about 0.1 micron to0.5 millimeter.
 3. The method of claim 1 wherein the thickness of thedisposing is about 0.3 micron to 25 microns.
 4. The method of claim 1wherein the disposing is accomplished by printing.
 5. The method ofclaim 4 wherein the printing is gravure printing, flexographic printing,or inkjet printing.
 6. A method of forming a treated laminated packagingmaterial, comprising d. forming a cyclodextrin composition comprisingone or more radiation polymerizable monomers and about 0.05 wt % to 10wt % of a cyclodextrin inclusion complex based on the weight of thecyclodextrin composition, the cyclodextrin inclusion complex comprisingcyclodextrin and an olefinic inhibitor compound having the structure

wherein each of R¹, R² are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup and R³ and R⁴ are independently hydrogen or a C₁₋₁₆ hydrocarbylgroup with the proviso that at least one of R¹ or R² is methyl; e.disposing the cyclodextrin composition onto at least a portion of onesurface of a first packaging material at a thickness of about 0.01micron to 1 millimeter to form a coating; f. exposing the coating toelectron beam radiation to form a treated packaging material; and g.contacting the coating with a second packaging material.
 7. The methodof claim 6 wherein the treated laminated packaging material is permeableto water on at least a first side thereof.
 8. The method of claim 6wherein the treated laminated packaging material is permeable to theolefinic inhibitor on a first side thereof and is impermeable to theolefinic inhibitor on a second side thereof.